You are correct in stating that the dimmer settings do not take effect until the player is started. First it will boot at full brightness. Then the dimmer setting will kick in when the player is launched.

Also, I don't think the "dimmer settings getting clobbered by the upgrade" problem happened to everyone. In fact, which user settings were getting clobbered seemed to be somewhat random. Some people it was the EQs, some it was the loudness, etc.