If I may help, as a new MorphOS user, I was in the exact same situation :)

Use DaPlayer (WildMidi, unfortunaely, gives horrible sounds).

With DaPlayer, you just have to download GUS patches, put them wherever you want and modify timidity.cfg (in DaPlayer's drawer) to point to where your patches are. And voilà ! You can hear MiDi files with excellent rendering.

And BTW, DaPlayer can also read lots of MOD music formats (and OGG / MP3 of course).

For me, this is the utimate audio player for MorphOS.

(I do use ANR only for web radios.)