When I replaced fiveam-tester-system with :fiveam-tester-system or "FIVEAM-TESTER-SYSTEM", the load went fine for me with the latest ASDF on Allegro, SBCL, and ABCL 1.5.0.

Really, no one should be running with an ASDF that's older than 3.2 these days. I thought that all the OSS lisps were distributed with at least 3.2 now. Why are you running with 3.1.x?

Best,
r