You need to open Google Drive to Remove or Delete a document in a Room.
To open Google drive: In the Room concerned, Click on the Drive (1) Tab => Move your mouse on the + menu at the bottom right => Click on Open in Drive (2)
You are now in Google Drive, inside the drive folder created for the Room. Google Drive gives you 2 choices:
1/ Move the selected File to another folder in Google Drive (1). The sharing permissions will be changed to the new folder sharing settings. If the new folder is a subfolder of the folder WizyRoom, the file will be accessible from the Drive folder of the selected room inside WizyRoom
2/ Delete (2) the selected File. It will be moved out of the Google Drive Folder to the Google Drive Bin. Sharing settings stay unchanged until the File is permanently deleted inside the Google Drive Bin
The file will be deleted from WizyRoom / Drive Tab / Google Drive view BUT will the still appear in WizyRoom / Drive Tab / File upload History view.
If you want make sure that Room members lose all access to the file, make sure you move the file to another folder where they don't have access.