First things first:
WADedit. (under ReinCARnation files)
WADEdit was made for DOTP 2013 (another title by Stainless). Uses same WAD format as Carmageddon Mobile and upcoming ReinCARnation.
Allows to unpack the data and mess around with the files. Not much to do so far. Not even sure we can pack it back up again after edition. (can't test here as I don't have an iThing, just grabbed the data from iTunes)
Textures files aren't TIFF or DDS anymore, seems like compressed PNG/Apple's PNG. Text files aren't encrypted. Sounds are just WAVE. ACT/DAT/MAT stuff still present, different extensions, different formats. Should be easy to figure out.