Multiple instrument selections

Is there a way to return the index numbers of instruments in a multiple selection? I can get a single instrument index using but this doesn’t work on multiple selections, is that possible?

No that is unfortunately not possible.
It would indeed be nice to get back an array of selected slots, but perhaps this will be added in the ((very) far) future.

Hope its not too far into the future!

So I guess the only way to select multiple instruments for processing would be to create a dynamic GUI with checkboxes that keep in sync with the loaded instruments?
It would be useful if there was some kind of list object in the GUI.