I was warned to choose ROM for 2.3 , which ends with 512. I took ROM
U8800Pro V100R001C00B512G001(Gingerbread) Firmware has to be 512!!!!
The most important advice for me was
Make a “dload” directory on SD card root directory , Copy the “Step 1\
dload\UPDATE.APP” and “Step 1\ dload\UPDATE_g.APP” to SD card
“dload\UPDATE_g.APP[”.
I copied UPDATE.APP to SD card in dload folder but didn't rename the file into UPDATE_g.APP!!!! I didn't understand the instructions corectly.
After that Settings/Storage/Software Upgrade
The next step is without renaming UPDATE.APP.
I didn't need step 3, because I don't speak Chineese.
After that relevation everything went smoothly and problemless.
After that upgrade to 4.0 went ok without any problem.