Strange selector switch for MGC metal M16 (early version)

From a certain deact website:







Is it because of technical limitations (MGC designers/engineers can only set the firing mode like this at the beginning) or caused by the lack of information back then ?

I have been asking this question myself for years. I am not sure about this, but my guess is that MGC took the easiest way to make a "M16-look-alike" model that was full metal and operational with caps. The locking mechanism with the big allen screw where the forward assist should be located was a big trade-off and much more obvious than the "flase" selector positions, as well as the whole firing mechanism that hardly resembles the real AR-15/M16 mechanism. Maybe one of our Japanese members knows more.