Installation on RAID 0 and uninstallation of Boot Mgr

[Henrik Zagerholm]

Hi all!
Having problem with installing 5.2.1 on a computer with 2 SATA 80G disk 
in RAID 0 (Striping)
There is a WinXP installed already which has 4 primary partitions of 5, 
10, 25 and 60G.
My BSD installation went like usuall. I chose to create a Slice on ar0 
in the unpartitioned 50G space. Then I chose to install Boot Manager.  
When commitin the changes a got error like "node for 'X' slices failed" 
,"mount /dev unavailable". I will give you the exact error messages if 
you need them! Then I had to reboot my machine and I got very suprised 
that  the boot manager was installed showing:
F1 ???
F2 ???
F3 ???
F4 ???

Which probaly means my 4 NTFS partitions. XP boots if I choose F1.  So 
my questions are:
1. How do I install BSD on my current RAID 0 system
2. How can I remove Bootmanager if I dont succeed with my BSD installation?

Sincerely yours,
Henrik