+1
You could try one of the guitars that have Direct Input and use those Holds then add Amplitube after it.
You could use a midi guitar holds then use a Direct Input Tele.sfz that I added in the UserTracks forum in Sforzando and add Amplitube after it.

I could make up some UserTracks with held strum and held single notes.
"Don't start a new riff on this bar"
would be used on bar 2,3,4 of a 4 bar held chord so those bars won't be used to to start a new chord, so if the chord starts on bar 1 enter 2-4, and if it starts on bar 5 enter 6-8, bar 9 10-12
so in the box would be 2-4,6-8,10-12, etc..
Direct Input would be best but if you could upload a pic of Amplitube settings that could be applied.

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