that app has nothing to do with OP's request. the app you linked is to keep root after a OTA update.
OP's request is to take out "root check" in the app. I guess the reason why they have it is the same reason why Google "Play Movies" doesn't allow rooted phones to watch movies because of DRM etc etc.
A workaround is to temporarily disable root.
Nexus 4 (E960): CarbonRom Nightlies | Franco Kernel (latest nightly)
ASUS Transformer (TF101): Team EOS4 #150 | K.A.T. 90
Older phones: Galaxy Nexus, Nexus S, Samsung Vibrant, G1