Beam engine operating

The Bolton 12 beam engine has now had some “running in” time, and I have made some tuning adjustments to the valve timing.
Is it now running more smoothly on low pressure compressed air. For the video the compressor is turned off, and the engine RPM falls off as the tank pressure goes down.
I do not have a boiler big enough to run this engine on steam, and I am negotiating with a friend to borrow his boiler so I can make a video of the engine running on steam. (Stuart, are you reading this?)