-current xenocara with radeonhd?

[macintoshzoom]

After updating to OpenBSD 4.4-current (GENERIC.MP), rebuilt userland, 
updated /etc and dev/, now I will have to build xenocara (that's, it 
seems as a tweaked X.org by OpenBSD):
Will I risk to never be able to restart my X after so many efforts to 
tune kdm, kde, my custom themes and styles, etc!??

Do I have to build/install xenocara before or after updating my ports 
and packages?

If my xenocara build fails, Is there a way/script (how?) to preserve my 
current X system and settings as a backup?
If it fails, how do I use this backup to restore (any script?) my old 
(but working good) X?

I am on an "ATI Radeon HD 2400 Pro" which should benefit a lot from the 
newest radeonhd driver that I have read somewhere latest xenocara 
supports: Any of you succeeded with the radeonhd?

Thanks again to all!

Mac.