Default [Q] Merging two custom roms.

I have recently used Baidu Cloud custom rom and another custom rom for my device (XOLO A500S).
The problem i found out is that, in baidu cloud custom rom there is no engineering mode. Code like *#*#3646633#*#* and app like mtk engineering mode doesn't work. It says "no engineering mode app found". I tried to add EngineerMode.apk and EngineerModeSim.apk to the baidu rom in system/app from other custom rom. But this doesn't work. Can anyone tell me whether is there any other library files that is needed to add from other folders. All suggestions are most welcome. Please help.