Default [Q]Building advice?

Hi guys, I'm trying to build Omni ROM and using the instruction provided by the Omni Team I setted up everything as it should be. The problem is that when I launch the command "brunch xt1032" after about 3 minutes the build process stops with this error:

make: *** No rule to make target `/Volumes/android/omnirom/out/host/darwin-x86/bin/dtbTool', needed by `/Volumes/android/omnirom/out/target/product/xt1032/dt.img'. Stop.
Anyone can help me to solve this problem?