Hello guys, perhaps this is the last comment from OP here..
After 24hr of testing, it seems with latest update (version .62) the problem has resolved. The difference with version .46 that the brightness level or limit is a bit brighter with this update (.62). I can say on version .46 it's great when you're in a pitch black room because the sensor automatically reduced to the lowest brightness. For version .62, it's best when you're in a room with normal or brighter lighting. If I can suggest, take or combine .46 and .62 adaptive brightness patch to the next update and I can assure we can have the best brightness sensor or auto brightness settings on Zenfone 8.
For random reboot, so far not experience it anymore. Although on previous crappy version (.56), my device reboot randomly for 3 times and after that...no more. Strange...
That's all folks!