I was basically saying that you could edit the Adria.ini file that is inside the installation folder. Change the "DataFolder" to a subfolder of the installation directory instead of the default (path that is somewhere in documents and settings).
As for your screenshot: the adria ingame window is in the wrong position and your d2 window isn't fully visible. Firstly move the d2 window so that it fits on the screen and then see if you can get the adria ingame window to correctly position itself before you hit insert. Correct position being in one of the upper corners. You may have to restart adria or just "mouse" the window for it to reposition itself.
Also, I'm not sure if it could be it but try only to use account and character names that you're actually allowed to use on bnet, we've had a few problems when the names are to strange.
Hmm, I haven't really tested really long tradelists much, but 60000 is the maximum you may have in one post on these boards iirc so I put it in that "warn me if longer" function to notify users of that.
It should work to have longer ones ... when considering the functions that make the lists. My guess is that it's probably a string variable limitation that I didn't think about when making them (maximum string size = 64K). But if you're getting spaces after that limit that is kinda strange.
For now I'd guess it's better to just split it into two lists.