sounds like you've tried to flash/downgrade checkrom over ICS without doing a full wipe (in recovery mode, wipe dalvik/wipe cache/wipe data). its managed to flash the CF root kernel of checkrom correctly but the rest of the rom has got mangled with ICS.
going by your above post, it appears you did you make a nandroid (full system) backup via CWM. in recovery (hold volume up+power+home), go to the restore and backup section and see if there is anything listed. if there is a backup listed (will show date and time of backup), use this to get back to where you started.
or...if you can, go back into recovery, select install zip from internal sd card and select the checkrom.zip. *make sure you do a full wipe first* (see above). and flash that. be warned!!! you will be reverting back to gingerbread 2.3.6 and will lose ICS (not a bad thing, i assure you.)
if all goes well, use your titanium backup to restore your apps etc. select restore apps and data, but i'd advise not restoring any backed up system data.