No Root on AOKP ROM topic

I'm using an unofficial port of AOKP 4.4 on my Xperia Miro. I'm having trouble with root permissions. I can see the Superuser tab in System Settings but it's unable to allow root access to any app. I tried flashing the superuser binaries and SuperSU but they did not work. I've also tried using RootMaster and UnlockRoot Pro.
The developer of the ROM has abandoned the device, so I was wondering if there was any simple method I could use to fix the root permissions myself. Android Kitchen seemed too complicated to use.

Thank you.