Weird, not working for me.
Downloaded, unziped it, copied to the sdcard, ran the file hiddenmemu.apk
Rooted and Knox disabled
Copied to the sdcard, installed twrp manager, reboot, choose install from sdcard, says the signature is wrong or whatever, anyways do the installation , same issue, not new features.
If you meant you tried to flash the MA7 to unlock the PRL writer, you dont zip the zip file that you download. jiust put the zip file any where and then flash it with cmw or twrp.
The zip file PRLWUnhide_MA7 works for MA7, MC2 and MK4.
However, you need the MSL code to get into the PRL thing. Go here: https://play.google.com/store/apps/details?id=com.patternedsoftware.getmymsl&hl=en. Then, do little research you will figure it out.