My HD0 and HD1 are filled up with 2 Win7 instances and numerous data partitions, all managed by BING. Wanted to clean install Windows 8 to a newly added HD2. Carefully followed this article in the knowledge base:http://www.terabyteunlimited.com/kb/article.php?id=339
When the Win8 installer (custom install) showed all partitions and I selected the one created before using BING, I got this error message: "We couldn't create a new partition or locate an existing one. For more information, see the Setup log files." Neither existing partitions nor unallocated space on HD2 were accepted as targets!
Looks like Win8 wants to put something on the HD which comes first in boot sequence, perhaps its 350MB System Reserved partition. I wanted to prevent this from happening by leaving no free space on HD0 and HD1 and declaring all their partitions as hidden in my Win8 boot item in BING.
It took me quite some time to find this workaround: Before booting the Win8 DVD, put the Win8 target drive (in my case HD2) BEFORE HD0 and HD1 in the BIOS boot sequence. Now Win8 accepted the existing partition on HD2, installed without creating a System Reserved partition and - even more important - without destroying anything on HD0 and HD1.
After successful Win8 installation I reset the BIOS HD boot sequence and reactivated BING.
I'm enjoying my triple-boot Win7-Win7-Win8 machine.