So the question is, is CWM working properly.No no, custom recoveries don't need root to do a proper factory reset. Or I'm pretty sure they don't. It also wouldn't lock your device (brick?). I made a nandroid backup using a custom recovery before I was rooted, nothing went wrong. I would expect a factory reset should be fine as well
If it is, not such a big problem (check xda, I saw a thread for this phone there about backing up the IMEI and NV stuff).
But if CWM is not working properly, and you start the rom install with a full wipe, you've got nothing.
If you start with a factory data reset, you'll only wipe /data and /cache, not /system.
/data you don't care about if back up everything with Titanium Backup.
/system you do care about - you want to wipe that before installing a rom (roms contain at most /system and the boot image). Otherwise, you're going to have an unhealthy combination of old and new in /system.
And if CWM is broken, then you'll have a phone with no operating system.
I get it.
And if this were an HTC, I could get you around that in a snap. But it ain't so I can't.

