As I understand it in the case of apollo, it (knowing the number of machines) can actually be beneficial to total render time. I was afraid it was going to be something like needing to have one node get access to bsi files from other nodes, but Albert says just knowing the number is enough for this particular optimization.
Regarding bsi auto-naming using guids, I think I’d leave that up to the user, via –finalBsiName. At least to start with. Probably I have not mentioned yet that when things are a bit more clear, I will add macro support for filenames and such, in which case a $guid macro would do the trick.