The number font in the corners and the lighting effect absolutely disregard the 160x144 and 4-color rules, but it appeared the rest followed it well.
I quickly got annoyed that running into a wall blocked movement parallel to a wall as well. You had to back up a step to move any other direction.
There seemed to be something to collect while avoiding the weird monster thing, but it was unclear to me what or how much of the things to collect.