Found some background info about the controller and relay box. they are both off-the-shelf components manufactured by JIECAN

Controller spec - http://www.jiecang.com/upload/file/enPDF/JCHT35K.pdf

and Relay spec - http://www.jiecang.com/upload/file/enPDF/JCB35N.pdf

I couldn't resist opening the remote. This is what i know about the pinout -

1. Transparent - "M" button (when set to LOW)
2. Brown - Digital - guessing it`s for data display (5v TTL)
3. Black - GND
4. White - ?
5. Red - +5v
6. Purple - ?
7. Green - UP button (when set to LOW)
8. Yellow - DOWN button (when set to LOW)

Next, doing some bit sniffing for the display.