I am actually the one who asked bwk for his test suite, which he later put on github. I started with some gawk tests while waiting for the test suite, however.
As for plan9's awk, it runs on ape. I am trying to make it run without ape. I had thought of starting with the latest version of awk, but boyd's port was nearly complete (it's in contrib). All I've been doing is making small bugfixes here and there. I'm not finished yet, but it won't be too much longer, hopefully. Perhaps after that I can take a look at the latest awk.