hap ac lite can't connect to another AP

That 5 euro AP/repeater thing (Edimax, TP-link, etc etc) knows 2 relevant modes mostly: AP and repeater. They call that repeater mode also “station” mode. That station mode is the Mikrotiks “station pseudo bridge” mode however. And they have also their problems … sometimes they work, and then with others AP’s they don’t work. And apart from selecting one of the 4 to 6 predefined modes you have no tools to check or correct.

Things reacted different since ROS 6.38 around DHCP. Maybe your old rb433 was on pre-6.38 release. (http://forum.mikrotik.com/t/ros-6-38-serious-dhcp-server-problem/105259/1) (http://forum.mikrotik.com/t/tp-link-repeater-re450-not-assigning-ip-address/118970/1)