It's probably too late for you now, but untarring the image you have been working with would have preserved all your additional installs.
I'm sorry I haven't been around much... Things remain stressful here in Qole's World I have some instructions on copying the contents of your image file into a dedicated partition in a couple of places. If you don't mind starting fresh, I have a recent post in the Diablo thread about how to dump a rootfs tarball into a partition. (You need to type tar instead of gtar, but otherwise they're the same on the N900). The instructions for dumping the file system from your image to a partition are also around here somewhere; I'll try to find them... I really need to make that into a wiki page...
Found it. Read this post and the update following it.