Yeah that’s what the delay parameter in the panel properties does, all messages are delayed by a certain specified time, it’s sort of a GAP between messages. the bigger the gap the less messages will be sent in the same period of time.
I tested it yesterday and it seem to work. This can’t be platform dependant because it uses a JUCE thread and a JUCE timer to queue the message, any low level OS specific MIDI stuff is done after all that.