I realize that, I guess the question better stated would be if I have issues again after I try to install, can I format system and reload a current clockwork mod backup to be where I started from now and be back to where I am now?The best thing to do is to first back up Apps with a backup program like Titanium Backup then after flashing the ROM you can restore just the apps. I do not recommend restoring system data or you might introduce some force closures.
Make sense?
Thanks!