You can select the individual default layout for each user to be displayed after they launch Web Client.

If you don't set this layout, they'll see a blank screen.

To set the default layout, do as follows:

1. Go to the desired layout.
2. Click  and select Use by Default.
   
   After that, the layout icon will look like this:
   

To remove the default layout, click  and select Do not use by default.