Coleco add Super Action Controller

Can someone help ? With Bluemsx and the colecovision, it’s impossible to have the 4 buttons of the Super Action Controller to play games like Rocky (No block & Duck).

Super Action Controller give 2 more buttons and i know how. On a real CBS Colecovision, these 2 buttons are 0+1 and 2+3 (“press” at the same time)

Is it possible to add this to retroarch ? I have no success to do it when mapping buttons or create a specific cfg file.

Please help, how to map 2 buttons on 1 input ?

Was the SAC ever added? I’ve been going nuts all day trying to get the purple and blue buttons to work in Frontline.