diff --git a/FrontEnd/src/app/groups/group-details/group-details.component.html b/FrontEnd/src/app/groups/group-details/group-details.component.html
index 7c9ba16..1b05cea 100644
--- a/FrontEnd/src/app/groups/group-details/group-details.component.html
+++ b/FrontEnd/src/app/groups/group-details/group-details.component.html
@@ -57,12 +57,12 @@
     [contentStyle]="{'min-height':'600px', 'min-width': '800px'}">
     <div *ngIf="dataToDisplay === 'testów'">
       Od kiedy test ma być dostępny:
-      <p-calendar [(ngModel)]="dateFrom" [showTime]="true"></p-calendar >
+      <p-calendar [minDate]="minDate" [(ngModel)]="dateFrom" [showTime]="true"></p-calendar>
       <br /><br /><br />
       Ile minut ma być dostępny ten test:
       <input type="number" step="1" min="1" name="howLong" [(ngModel)]="howLong" />
       <br /><br /><br />
-      <button class="button" (click)="editTestAvailability()">Edytuj</button>
+      <button [disabled]="howLong < 1" class="button" (click)="editTestAvailability()">Edytuj</button>
     </div>
     <div *ngIf="dataToDisplay !== 'testów'">
       Ta funkcjonalność pozwala tylko na edycję dostępności testów.
diff --git a/FrontEnd/src/app/groups/group-details/group-details.component.ts b/FrontEnd/src/app/groups/group-details/group-details.component.ts
index 11789dd..d60485d 100644
--- a/FrontEnd/src/app/groups/group-details/group-details.component.ts
+++ b/FrontEnd/src/app/groups/group-details/group-details.component.ts
@@ -31,15 +31,17 @@ export class GroupDetailsComponent implements OnInit, OnDestroy {
 
   displayAvailability = false;
 
-  dateFrom: Date;
+  dateFrom: Date = new Date();
   howLong = 10;
   testId = 1;
 
+  minDate: Date = new Date();
+
   columnDefs = [
     { headerName: 'Nazwa', field: 'title', headerTooltip: 'Nazwa' },
     { headerName: 'Ocena', field: 'grade', headerTooltip: 'Ocena' },
     { headerName: 'Max.', field: 'maxScore', headerTooltip: 'Max.', hide: false  },
-    { headerName: 'Rozpoczęcie testu', field: 'startDate', headerTooltip: 'Rozpoczęcie testu' },
+    { headerName: 'Start', field: 'startDate', headerTooltip: 'Start' },
     {
       headerName: '',
       suppressMenu: true,
@@ -49,6 +51,8 @@ export class GroupDetailsComponent implements OnInit, OnDestroy {
   ];
   timetest: number;
 
+  timeout: any;
+
   constructor(private route: ActivatedRoute, private groupService: GroupsService, private router: Router,
     public snackBar: MatSnackBar) { }
 
@@ -89,7 +93,8 @@ export class GroupDetailsComponent implements OnInit, OnDestroy {
       success => {
         this.snackBar.open('Prawidłowo edytowano przedział czasowy.', null,
           { duration: 3000, verticalPosition: 'top', panelClass: ['snackbar-success'] });
-          this.displayAvailability = false;
+        this.displayAvailability = false;
+        this.isDisplayed('testów');
       },
       error => {
         this.snackBar.open('Wystąpił błąd serwera. Spróbuj ponownie później.', null,
@@ -128,7 +133,9 @@ export class GroupDetailsComponent implements OnInit, OnDestroy {
       const timetest = temp.getTime();
       const tempstop = new Date(data['dateTo']);
       const timeteststop = tempstop.getTime();
-      if (timetest < now && now < timeteststop ) {
+      const currentUsername = JSON.parse(localStorage.getItem('currentUser')).username;
+      const groupOwnerUsername = localStorage.getItem('groupOwnerUsername');
+      if ((groupOwnerUsername === currentUsername) || (timetest < now && now < timeteststop)) {
       switch (actionType) {
         case 'remove':
           return this.onActionRemoveClick(e);
@@ -152,7 +159,7 @@ export class GroupDetailsComponent implements OnInit, OnDestroy {
   }
 
   noTime() {
-    this.snackBar.open('Test jest jeszcze nieaktywny.', null,
+    this.snackBar.open('Test jest nieaktywny.', null,
     { duration: 3000, verticalPosition: 'top', panelClass: ['snackbar-error'] });
   }
 
@@ -225,32 +232,52 @@ export class GroupDetailsComponent implements OnInit, OnDestroy {
   }
 
   onGridSizeChanged(params) {
+    const currentUsername = JSON.parse(localStorage.getItem('currentUser')).username;
+    const groupOwnerUsername = localStorage.getItem('groupOwnerUsername');
     if (params.clientWidth < 800) {
-      this.columnDefs = [
-        { headerName: 'Nazwa', field: 'title', headerTooltip: 'Nazwa' },
-        { headerName: 'Ocena', field: 'grade', headerTooltip: 'Ocena' },
-        { headerName: 'Max.', field: 'maxScore', headerTooltip: 'Max.', hide: true },
-        { headerName: 'Rozpoczęcie testu', field: 'startDate', headerTooltip: 'Rozpoczęcie testu'},
-        {
-          headerName: '',
-          suppressMenu: true,
-          suppressSorting: true,
-          cellRenderer: this.customCellRendererFunc
-        }
-      ];
+      if (groupOwnerUsername === currentUsername) {
+        this.columnDefs = [
+          { headerName: 'Nazwa', field: 'title', headerTooltip: 'Nazwa' },
+          { headerName: 'Ocena', field: 'grade', headerTooltip: 'Ocena' },
+          { headerName: 'Max.', field: 'maxScore', headerTooltip: 'Max.', hide: true },
+          { headerName: 'Start', field: 'startDate', headerTooltip: 'Start'},
+          {
+            headerName: '',
+            suppressMenu: true,
+            suppressSorting: true,
+            cellRenderer: this.customCellRendererFunc
+          }
+        ];
+      } else {
+        this.columnDefs = [
+          { headerName: 'Nazwa', field: 'title', headerTooltip: 'Nazwa' },
+          { headerName: 'Ocena', field: 'grade', headerTooltip: 'Ocena' },
+          { headerName: 'Max.', field: 'maxScore', headerTooltip: 'Max.', hide: true },
+          { headerName: 'Start', field: 'startDate', headerTooltip: 'Start'},
+        ];
+      }
     } else {
-      this.columnDefs = [
-        { headerName: 'Nazwa', field: 'title', headerTooltip: 'Nazwa' },
-        { headerName: 'Ocena', field: 'grade', headerTooltip: 'Ocena' },
-        { headerName: 'Max.', field: 'maxScore', headerTooltip: 'Max.' },
-        { headerName: 'Rozpoczęcie testu', field: 'startDate', headerTooltip: 'Rozpoczęcie testu'},
-        {
-          headerName: '',
-          suppressMenu: true,
-          suppressSorting: true,
-          cellRenderer: this.customCellRendererFunc
-        }
-      ];
+      if (groupOwnerUsername === currentUsername) {
+        this.columnDefs = [
+          { headerName: 'Nazwa', field: 'title', headerTooltip: 'Nazwa' },
+          { headerName: 'Ocena', field: 'grade', headerTooltip: 'Ocena' },
+          { headerName: 'Max.', field: 'maxScore', headerTooltip: 'Max.' },
+          { headerName: 'Start', field: 'startDate', headerTooltip: 'Start'},
+          {
+            headerName: '',
+            suppressMenu: true,
+            suppressSorting: true,
+            cellRenderer: this.customCellRendererFunc
+          }
+        ];
+      } else {
+        this.columnDefs = [
+          { headerName: 'Nazwa', field: 'title', headerTooltip: 'Nazwa' },
+          { headerName: 'Ocena', field: 'grade', headerTooltip: 'Ocena' },
+          { headerName: 'Max.', field: 'maxScore', headerTooltip: 'Max.' },
+          { headerName: 'Start', field: 'startDate', headerTooltip: 'Start'}
+        ];
+      }
     }
 
     params.api.sizeColumnsToFit();
@@ -301,7 +328,10 @@ export class GroupDetailsComponent implements OnInit, OnDestroy {
     }
     if (resource === 'testów') {
       this.localeText.noRowsToShow = 'Brak testów do wyświetlenia';
-      setTimeout(() => {
+      if (this.timeout) {
+        clearTimeout(this.timeout);
+      }
+      this.timeout = setTimeout(() => {
         this.testsSubscription = this.groupService.getResource(this.id, 'tests').subscribe(data => {
           this.data = data;
           data.forEach(x => {
@@ -310,11 +340,15 @@ export class GroupDetailsComponent implements OnInit, OnDestroy {
             x['startDate'] = '';
             const hours = temp.getHours();
             const minutes = temp.getMinutes();
-            const months = ['STY', 'LUT', 'MAR', 'KWI', 'MAJ', 'CZE', 'LIP', 'SIE', 'WRZ', 'PAŹ', 'LIS', 'GRU'];
-            const year = temp.getFullYear();
-            const month = months[temp.getMonth()];
+            // const months = ['STY', 'LUT', 'MAR', 'KWI', 'MAJ', 'CZE', 'LIP', 'SIE', 'WRZ', 'PAŹ', 'LIS', 'GRU'];
+            const year = temp.getFullYear().toString().substring(2);
+            const monthTemp = (temp.getMonth() + 1);
+            let month = monthTemp.toString();
+            if (monthTemp < 10) {
+              month = `0${monthTemp}`;
+            }
             const date = temp.getDate();
-            const time = date + ' ' + month + ' ' + year + ' ' + hours + ':' + minutes;
+            const time = date + '.' + month + '.' + year + ' ' + hours + ':' + minutes;
             x['startDate'] += time;
           });
         });
diff --git a/FrontEnd/src/app/groups/sharing-resources-in-groups/sharing-resources-in-groups.component.html b/FrontEnd/src/app/groups/sharing-resources-in-groups/sharing-resources-in-groups.component.html
index 46162e9..e6240a5 100644
--- a/FrontEnd/src/app/groups/sharing-resources-in-groups/sharing-resources-in-groups.component.html
+++ b/FrontEnd/src/app/groups/sharing-resources-in-groups/sharing-resources-in-groups.component.html
@@ -28,13 +28,13 @@
         <div *ngIf="testsToAdd.length > 0">
           <br /><br />
           Od kiedy test ma być dostępny:
-          <p-calendar [(ngModel)]="dateFrom" [showTime]="true"></p-calendar>
+          <p-calendar [(ngModel)]="dateFrom" [minDate]="minDate" [showTime]="true"></p-calendar>
           <br /><br /><br />
           Ile minut ma być dostępny ten test:
           <input type="number" step="1" min="1" name="howLong" [(ngModel)]="howLong" />
         </div>
         <br /><br />
-        <button [disabled]="selected.length === 0" class="button mr-1" (click)="addResources()"><i class="fas fa-check-circle"></i> Dodaj</button>
+        <button [disabled]="(selected.length === 0) && (howLong < 1)" class="button mr-1" (click)="addResources()"><i class="fas fa-check-circle"></i> Dodaj</button>
       </div>
       <div *ngIf="!(materialsToAdd.length > 0 || flashcardsToAdd.length > 0 || testsToAdd.length > 0)">
         Brak elementów do dodania
diff --git a/FrontEnd/src/app/groups/sharing-resources-in-groups/sharing-resources-in-groups.component.ts b/FrontEnd/src/app/groups/sharing-resources-in-groups/sharing-resources-in-groups.component.ts
index cd1c241..1f37682 100644
--- a/FrontEnd/src/app/groups/sharing-resources-in-groups/sharing-resources-in-groups.component.ts
+++ b/FrontEnd/src/app/groups/sharing-resources-in-groups/sharing-resources-in-groups.component.ts
@@ -15,9 +15,9 @@ import { Subscription } from 'rxjs/Subscription';
 export class SharingResourcesInGroupsComponent implements OnInit, OnDestroy {
 
   public id = 0;
-  public dateFrom: Date;
+  public dateFrom: Date = new Date();
   public howLong = 10;
-  public maxDate = new Date();
+  public minDate = new Date();
 
   public materialsToAdd: Resource[] = [];
   public testsToAdd: Resource[] = [];
diff --git a/FrontEnd/src/app/login/login.component.css b/FrontEnd/src/app/login/login.component.css
index c517f10..bc597e5 100644
--- a/FrontEnd/src/app/login/login.component.css
+++ b/FrontEnd/src/app/login/login.component.css
@@ -1,5 +1,5 @@
 #container-small {
-    background-color: #181616;
+    background-color: #28102f;
     padding: 30px;
     width: 25%;
     height: 400px;
@@ -10,7 +10,7 @@
     text-align: center;
 }
 #container-login {
-    background-color: #181616;
+    background-color: #28102f;
     top: 50%;
     left: 50%;
     transform: translate(-50%, -50%);