Tom,
We'll switch gears to the "old" WS12a.
Since initially you did not see your lamp brighten or dim (after the 5 minute period) you may have had a power upset that left your flag enabled. This would prevent activating the macro when you walked up.
When you manually activated the macro, it would bypass the conditions and, at the end, reset the flag.
The next time this occurs, check your activity monitor to see whether the macro tried to execute. If it doesn't, it might be due to a flag problem. If it executes, but doesn't activate the lamp, it's most likely noise.
Rather that using a "relative brighten to 100%", try using an "absolute 100%". This should use a simple "ON" command - much faster and easier on your repeater.
Boiler