Maybe try to ignore CPANPLUS test files, like harness -v "-re=(?!CPANPLUS)"

Thanks, cd'ing to the t directory and running perl harness -v "-re=(?!CPANPLUS)" seemed to do the trick.
There were a few failures in one of the EU::MM test scripts (basic.t, iirc) - other than that, all was fine.

Cheers,
Rob