Maybe it’s the same bug:
If you load a midi file (yes this works in Renoise), the first instrument will be a sample, but should be also a midi instrument.
If the template song is loaded at start or new song, the saved selected instrument will be a sample, no matter if it’s a sample or not. If you select then another instrument and then selected the first selected instrument, the type will now be correct.
If you load a midi file (yes this works in Renoise), the other instruments a plugins, I guess they should be ext. midis?