Hi Adam,
I'm kind of new to this so I certainly don't have the answers but I did break out my PalmPad and tried to recreate your situation but couldn't. Using the PalmPad and the TM571, a newer LM465 went to full on - even if previously turned off at a very dim level. I also tried this in my basement office with a different LM465 with the same results. The WS467 went to resume dim, but I was able to over-ride it using the PalmPad. I'm not sure why you can't get pass the 50% mark. Maybe Mellowmark has some ideas?
For my original issue, I noticed that when using the PalmPad to dim or brighten a WS467, the light level stepped in noticeable increments. I think for now I will just send 9 or 10 RF "brighten by 99%" macro commands to get my lights to bright - regardless of where they were turned off at.
I'll be anxious to hear the results of your CM11a test.
Good luck, Adam.
Patrick