Impossible to expose Root note as CV port in Carla

[Spraitazz]

while other discrete parameters such as Octave can. Can it be as simple as changing the type of parameter of Root note from list to discrete integer?

[sjaehn]

This is right. The root note is realized by two parameters (or to be precise: two lv2 ports): root and signature. Both are enumerations. root has got the range from 0 to 11 (from note C to B), but skips the values for the "signed" notes. signature has got values from -1 to 1. Thus, the sum root + signature is the number of semitones starting from C.

And indeed, enumerations can't be exported as CV in Carla. Exporting floats or integers from control ports to CV is a great feature of Carla. You may discuss with @falkTX if an export of enumerations makes sense too (or not).

Another option would be to merge root and signature to a single parameter. However, this would break the backward compatibility and can't be done for this plugin version. But it is a good idea for a B.SEQuencer2.