The idea is quite simple:
One instrument get the value of widget and store it in an bidimensional array where X dimension is the list of parameter and the Y dimension is different every time the preset is changed (write all the X in a different Y)
The effect instrument itself read the needed parameters in the corresponding array Y dimension, the instrument have a different fractional number at each preset change; tail is acheived by linsegr envelope; is like a polyphonic instrument with each voice reading a different array part.
Basically the instrument that read the widgets and the effect that use parameters must write and read the same Y array dimnsion.
Hope there was a simpler way
Biggest part of the code is due to the preset system I’m using (to have midi control), it should work also with the default preset mehod, maybe I’ll give it a try.