It is strongly recommended that you flash clockwork recovery via NVFlash. If for some reason this or a future nightly build causes your phone to not boot up, you will not be able to boot into recovery unless you have it flashed via NVFlash.
NVFlash for Linux
NVFlash for Windows
To clear up some confusion, if you flashed your recovery via ROM Manager, you didn't actually flash a recovery. It is what we call a fakeflash, you should still probably flash with NVFlash.
Download from http://download.cyanogenmod.com/?device=p999 and flash like you would any other ROM (via recovery or ROM Manager).
Be sure to backup before flashing, and of course a wipe is necessary when coming from stock.
Gapps are available from the usual places, however do not download the version that says it is for Tegra, even though this is a tegra device, as it will not flash.
Google Addon: http://goo-inside.me/google-apps/
Check the lastest package available on top
After skimming some of the posts in this thread, here are some things that you can expect.
What to expect
- Everything working including Wifi, GPS, Audio, Camera, Front Facing Camera
- Screen off animation is not enabled, therefore it isn't broken.
- Occasional audio problems (as far as I know they have not been fixed). If audio does not play just reboot.
- Automagical brightness weridness, this is controlled by the kernel and not userspace, even having it working is very hacky.