If you see the linux boot text, then black screen, you may have a corrupted OPK which makes gmenu2x to crash.
In that case, FTP to your unit and delete all the OPKs of your apps folder, then try to reboot.
If it still doesn't work, try to delete all the files inside the following folders:
I had encountered an issue while testing some legacy dingux apps where I got a black screen, but I was able to make the screen come back by changing sections (L or R). IIRC, it was the icon that I assigned which was causing the screen to go black, rather than the app itself (I think the problem occurred after assigning an icon).
Gmenu2x boots to the Applications section, so if changing sections brings the screen back, the offending OPK (or possibly just its icon) would be in that section, and the proper files to delete would be in /media/data/local/home/.gmenu2x/sections/applications/, right?
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