Thank you very much indeed!

The latency is set by the audio buffer size (on the audio tab of the settings screen). On my PC I can safely get it down to 8K, which equates to about 93 ms of latency. The speed of the computer will govern this.

Real pipe organs produce sound pretty much immediately, except where the pipes are located a long way from the console, in which case there is the time for the sound to travel. It is possible that pneumatic-action organs may have a slight delay, but I'm not certain.

Martin.