[Q] Change CM10.1 back to Stock rooted

Greetings.
Some months ago I got me an N7000 and was kinda happy with the original (rooted) rom.
I loved the multi-windows option of the 4.2.2 release. But I kinda got several slowdowns (maybe because of
some too many apps installed?), so I flashed to CM10.1.
To my disapointment there wasn't a statusbar at the top (where to conveniently choose wifi, etc) or any multi-window or s-note options.

My questions:
1.) Is there a way to enable multi window and editing the statusbar at the top or s-note?
2.) If the above isn't working out, how do I get back to the original samsung 4.2.2 rom that is still rooted?
Do I have to use Odin or similar programs, or are there easier procedures, and where do I find the rom files for flashing?
I found a manual:
http://itekblog.com/change-cyanogenm...tock-firmware/
Is this procedure save and sound, the way you would do it?

I DID make a nandroid backup on my ext.sd. Is it possible to reflash my prior rom with that, or is this "backup" just meant for apps and personal data?

I'd love to go back to how things were,...

Thanks in advance!