I’ve run into a couple of things in Gnome that are either impossible, or poorly documented; I can’t be sure which.
The first is trying to reset the bottom panel. I was playing with mine, and made a mess of it. I just wanted to get it back to its initial state, in other words, reset it. It’s possible to delete it, but if you add a new panel back, it’s empty.
I Googled for a while, and then tried to tackle the configuration files. I edited and/or removed files in ~/.gnome2, ~/.gnome2_private, ~/.gconf, ~/.gconfd and ~/.gnome. (I’ve been running gnome on this particular machine for years). The information is probably in /etc/gconf/schemas/panel-default-setup.entries, but I have no idea how to use it. Presumably I would have to merge the contents into some file in the directory ~/.gconf/apps/panel, but this has already eaten upwaay too much time.
The other annoyance is the seeming impossiblity of setting different font sizes for different displays. My console runs at 1280×1024, and I often connect from my windows box running the Cygwin X server at 1600×1200. I can choose fonts that are either too large or too small one the other display, but can’t seem to set font based on the display, or DPI setting, or display size.