[cells-devel] Error: Attempt to take the value of the unbound variable `MD-SLOT-CELL'

Hi - just downloaded newest Cells repo from github. Using AllegroCL 8.2 Express Edition on Windows 7 I get the error mentioned in the subject. I haven't looked into it, but strangely enough, I do get this from both Ramarren's and Kenny's repos. Any ideas ? Thx! Cheers Frank