17) press PB to map asui
28) press PB, screen was locked so it attempted to blank it
31) over and over you pressed it with same results
125) MMC access opened the blank window and unlocked keypad, waiting for secondary key to unlock
126) something enabled the screen as well, still
131) you pressed PB and it attempts to blank it
133) you touch screen which causes blank window to close but the PB finally relocks screen and keys but the blank failed
148) you press it some more
153) another MMC access and ASUI is waiting for secondary key
156) you pressed the dpad center key and unlocked the device
212) you turned off the secondary unlock key, thinking this would fix your problem, but the PB always blanks the screen when it is on and locked and since your screen isn't turning off there is no way to use PB to unlock screen since that only works when the screen is off.

Did you open/close the MMC door 6 times during that log period? USB port, headphone jack, charger and MMC all turn on the screen and unlock the device is secondary key not required, they will also unlock keys and prompt for secondary key if it is required. You could use any of these as a failsaife to unlock the device. Power button is not required to unlock the device, it is just one of many ways to access the secondary key sequence. Once you see the "press KEY to unlock" notification you just need to press the secondary key before the screen turns off.

Your problem is that MCE won't blank or dim the screen when ASUI asks it to. And if the screen never turns off then power button can never be used to unlock it. I could add a setting to disable the PB blank feature and have it always unlock or prompt for secondary key but that wouldn't help you because not having your screen blank is a much much bigger problem.

Alarm dispatcher can keep the display from blanking and the device from shutting down if an alarm is active or about to go active. You could using asui-setting app to stop alarm dispatcher and maybe remove it from boot sequence. Have you installed anything that the rest of us might not have?

Edit: It appears that whenever you press power button MCE unlocks the keys probably so SystemUI can get its secondary key to unlock screen. I was unaware it was doing this and it only happens for a 2 second period when the screen is on but locked and power button is pressed. This is why your keys are passing through, next release will fix this.