Thanks for your time Matty.
Can you point me to a good tutorial on making back-ups and nanadroids. The part i don't get is after the new ROM with Theme Manager is flashed , how do i activate the back-up?....really scared of losing my stuff.
Also, suppose i change only the icons alone and no theme. What if i want to revert? Would I need to download the original icons somewhere or are they in defaults?
Lets start with the icons since that's easier. There are two ways to reset your icons back to stock(Default). You can either long-press on an individual icon that you have changed then click the icon then click "restore default", or if you have used an icon pack from the market you can go to Nova Settings/ Look & Feel / Icon Theme and click on Default.
Now for backups. Other than Clockworkmod recovery there are two apps in the play store that are worth the money if you are going to flash AOKP and want all your data. The first is Titanium Backup and the Second is called AOKP Backup. Titanium will save all your apps and app data, while AOKP Backup will save all your AOKP system settings. I personally never wipe data when updating to a new version of AOKP. I can't say the same will work for you but I haven't had a single problem and I have been on AOKP since Build 20.
All you need to do is backup all your apps and data with Titanium Backup, Backup your AOKP settings with AOKP backup then boot into recovery and create a Backup with it. Now that you are backed up you can either just wipe cache, and dalvik cache then flash the new AOKP and Gapps without wiping data and see if you have any problems, or you can wipe data, cache, and dalvik cache and start fresh. Its your call. If you choose to wipe all you need to do is download Titanium backup from the market and once its installed you can open it and restore your apps. DO NOT restore system apps with Titanium Backup because it will more than likely cause issues. That is what you use AOKP Backup for. After your apps are restored it is a good idea to reboot your device. then you should be good to go. I hope this epic reply doesn't confuse the hell out of you. Let me know if any part of it confuses you.