Tried to recreate your error the best I could with your description. Copying a specific instrument from a midi block out of one Song Track, and pasting it into a different Midi Block in the second Song Track. I had no issues.

Are you selecting copy on the source Midi Block, and then right Clicking and selecting “Paste On Selected Blocks” + “HiHat”?

I don’t know exactly what “a saved midi” or “a Midi Saved” is. A whole song, just a part?

I’m was referring to a single midi block, from “Track 1” to “Track 2”. If it’s a whole song, import it, cut out the section you need to copy the hihat from, then copy/paste as I stated.

If you have two instances running side by side, I don’t know how to do that without a DAW, just drag the midi groove in question from one instance’s Songtrack to the other instance’s Song Track. Overwrite the part in question by dropping it right on top, or drag it to the end of your song (or new Song Track) and copy/paste the part.

Or you could drag just the part in question to your Superior User Midi, and access it there in your newer session. (bottom left folder on the Grooves Page).

“In your case, are both blocks in the same Song Tracks? I know that copy/paste between blocks works OK. SO does that mean that the best way to do my copy is to import the old MIDI into the same instance and Song Track (say) out at 140+ bars – then copy/paste accordingly between blocks / bars in the old to the new?”

Yes. And yes, that’s one way to do it.