In Netscape (which I tried first, intending to try to upload the Arabic-named file which I couldn't in Konqueror),...
Netscape 4.X has problems with the sidebar that I'm not going to fix, especially a version as ancient as 4.08. 4.7 was for a long time a mainstay of Unix machines, so I want the system to be usable there, but there's two ways to do that: don't use the quickbar at all (it can be turned off and the site should be quite usable without it), and move to Mozilla, which should be available on all those Unix boxes now.
In Konqueror, the navbar is on the left before logging in and on the right after. Nothing is covered up.
Sounds normal. Before you log in, the system uses default settings which are Standard skin and fixed-left quickbar. You probably have quickbar set to right in your preferences, so it moves after you log in. 0