I suggest u try to flash it by the patched version of window update program in hedgepigdaniel post.
If you want to restore it properly, then that would do it, But if the phone works now, then its an unnecessary risk. If you do want to do it, then you MUST do the following:
replace recovery.img in the firmware files with the correct (Gen1/Gen2) version of stock recovery for the Gen you are flashing to
either replace boot.img with the correct version of clockworkmod recovery, or put the stock China unicom boot.img and system.img and a blank userdata.img (if you are sure that it will boot)
If you don't do that, You will lose your IMEI or not be able to boot your phone