I'm trying to get the LaB HRP to work as well. When using the Caribbean.bat I receive this message:
Error: You don't have VACATION.GRP in your directory.
Aborting Launch.
Press any key to continue . . .
Well I've already used the unpackssi program to make group files of all three of the ssi files on my lab disk. I tried each one in my duke3d folder along with the duke3d.grp. No luck.