See the mod conflicts mentioned. Any mod that has it's own bulk materials (even Straw Harvest DLC or omaTana's Apple Orchard), uses an xml file and gdm image to register those bulk materials, but like the game, it has only 6 channels. The map to load so many crops and bulk types, has to had at least 7 channels for densityHeight...
For the moment I don't have a fix for this. The main cause for the problem is the engine itself. Giants offered the posibility for 64 crops, but decided to use base-game only 32. That means lower channels for bulk as well...