is ur target disk ide? or sata?
if ide u have to find a kext that will detect ur ide drives... as far as i can remember there were some modified ide kexts floating around that worked with snow... have a look around for those...
if ur target disk is sata, make sure it is running in AHCI mode... set it in bios...
if ahci is already enabled... try lauching the disk utility from the installer menu... if ur target disk is visible there, then everything is fine... u are able to select it as target from my script...
i used to get those uuid error 35 back in 10.5 but i simply ignored those...
if that may be the cause of ur target disk dissapearing, u will have to use a kext called "platformuuid.kext" and add ur disk uuid to that, or something like that... please search the forum for that info... cos i personally havent dealt with that...
lemme knoe how u go...
UPDATE: looks like the uuid 35 error doesnt have anything to do with missing drives... its related to a missing firewire network interface according to this:
http://forum.voodooprojects.org/index.php?topic=250.0