so this is a stupid problem. the sampler module doesn't run if your folder's path has a space in it. also, since the sampler reads in Dir_name (a relic of early work on the program), and it contains the data folder's absolute path, if a data folder is moved the sampler will break. ugh.
on a mac, you'll get this error:
libc++abi.dylib: terminating with uncaught exception of type std::runtime_error: invalid dimension of object to sample. you sure you have a valid decomposition?