Many of Faithful32's textures for Chisel Concrete and their various colors do not match the original Chisel textures. The concrete_black textures are also very dark and hard to make out detail unlike the original. The other texture folders such as cobblestone, diorite, endstone, glowstone, etc seem to be just fine though, just concrete is incorrect.

EDIT: The quartz folder also seems to have the wrong base texture, there's a noticeable tiling on all the textures