problem with maclaw CM11, constantly restarts

I have a problem with a custom rom, i have a galaxy s advance, which isn't supported by cyanogen mod. Maclaw has created kitkat roms for some devices which aren't suported by cyanogen. I now have his kitkat 4.4.4 rom running. Unfortunately maclaw hasn't got a forum. (they are setting up one but it isn't launched yet) So i decided to ask here, since you guys have knowledge about pretty much everything, regarding this subject. Maybe anyone else could point out what the possible cause of this problem could be. In my case, the phone restarts after a while, but only when the device is on battery, and when the screen is locked. Everything works perfectly when it's on charger and/or unlocked. Is this a common problem or does it have a well known cause? Thanks in advance for all your efforts.