nprofile1qy2hwumn8ghj7un9d3shjtnyd968gmewwp6kyqpqwl8sdcnqcrusekg4g8gwm807jyc8u2kjdpw9demm2gfj4esg0tkshl5h35 (nprofile…5h35) Hrmm... I found the "ProDOS Exerciser" disk in the Internet Archive and that works with relative paths. (ProDOS 1.0.1 apparently) If I boot from that disk and bload my code there, it works with relative paths. If I boot a more recent ProDOS (2.0 is was the oldest I tried) it doesn't... Bah! None of them seem to work with SmartPort disks.
I suppose I should start with a trivial replication project to rule out memory corruption.