Hello Florian,

You can change the content of the displayed tree in <your web site>\CMSDesk\MyDesk\ in the files:

leftmenu.aspx
leftmenu.aspx.cs

In general, if you want to customize the CMSDesk/CMS Site Manager, you can find the files which generate the page with the Firefox browser. You just have to left-click on the area, you want to change select "This Frame -> View frame info" and there are two paths. Usually the first one points to the file you have to change.

I hope this helps.

Best Regards,
Boris Pocatko.