@JacktheRipper. I'm intrigued by your motion sensor solution. Could you share the programs you described?
"I wrote a timer program, normally disabled, that turns the lights off after a time-out, set at 10 minutes. If the light switch or the MS II turns on the scene, the timer program is enabled and starts the timer. If the MS II detects subsequent motion, it triggers a second program that (1) sends an on command for the scene, (2) disables the timer program, (3) waits 5 seconds, then (4) re-enables the timer program and runs it. This refreshes the timer program to always time out 10 minutes after the last detected motion. When the timer program reaches the time-out, it turns the scene off, then disables itself."