Welcome aboard to the CD Freaks forum
I'm rather surprised there was not a restriction in place to prevent the accidental loading of a foreign firmware, since most other manufacturers will reject firmware that is not of the DVD Recorder's region, for example, a German model of the LVW-1105HC+ will not accept UK firmware. Another unusual thing is that going by the manual, there is no option to choose between PAL and NTSC on your model, so it seems like the hardware capability is there, but is controlled by the firmware.
Anyway, seeing that you managed to get PAL firmware installed, I would imagine that it should be straight forward enough to put back on the official firmware. While it may not have DivX support, having a picture is better than a B&W rolling picture with DivX support.
The following page is Cyberhome's official firmware download page:
Going by the firmware updating steps, it seems that all you need to do is select 'Yes' after loading the firmware update disc and even with a rapidly rolling picture, you should still be able to make out whether the 'Yes' or 'No' is highlighted. The tray will eject when the firmware update is complete, so even if you cannot see the firmware update progress on screen, at least you'll know when it completes.
Hopefully the official firmware update does not perform a check to see if firmware from a different region is present.