please, do NOT save files outside of own program directory and most of all NOT IN THE APPDATA!!! (also not in the registry, but rather registry than appdata)
and please also give a setup-free .zip to download (just the files zipped without any bloated setup routine)
and i would love to see tabs. i read in another thread about that there is already the taskbar with childwindows and stuff but still i like tabs more rather than multiple taskbar entries.
otherwise nice work