So here are my two critical issues that are the only things standing in the way of KDE on my n800:

1. The kdesu window that pops up when you try to change config stuff. To try to get by that, I went into a terminal window as root and actually set a root password. I verified that you can go into a normal terminal and issue an su command and get to the root prompt with it. But when that password is entered into the kdesu window, the window just freezes and you can't get any further. This is critical because KDE is displaying the wrong time on the taskbar (presumably a timezone config problem?), but you can't get into the config to fix it.

2. The right-click problem that I mentioned in another thread. You really need to be able to right-click in KDE, but the solution suggested by Penguinbait and PinCushionQueen (awk script assigned to a hotkey) doesn't work quite right for me. It toggles one way to turn on right-click, but won't toggle back.

I was using KDE from Penguinbait's "easy install", so I am not dual booting from MMC.