Sounds like whomever compiled the ROM did so using the "-eng" release instead of the more forgiving "-userdebug" variant.
Using what I happen to be on as an example, flo, this is where it appears in the build.prop.
"ro.build.display.id=cm_flo-userdebug 4.4.2 KVT49L 3134cc89db test-keys"
"If" yours says eng or anything else besides userdebug, simply changing it may not be good enough.
The above answer of adding those 2 lines may end up being your best answer but you might pass on what I said to the dev.
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