First I would suggest installing the generic version of 2.3.
So,
download the Flashtool -
http://azuzu.spice.net.au/tools/X10_GB_Root/FlashTool_0.2.9.1-GBready_root_xRec.exe
Install it, then go to
download the generic version of 2.3:
[Download] All X10 Firmwares - xda-developers
I downloaded X10a_3.0.1.G.0.75_AMERICA-US GENERIC 1233-8200.zip (140.5 MB)
Unzip the file and there should be a FTF file inside, that is the generic ROM
Open Flashtool,
Click Flash, navigate to the FTF file that you unzipped.
Chose it, it will prepare the FTF file and then open a window asking you to turn your phone on in Flashmode.
Turn off phone and then hold the back button and plug in the USB cable at the same time like the window is asking you to do.
It will flash the phone to generic 2.3