Even though it's listed as ``global'' in the HTK book, I was able to get rid of the "HMM Def Error: <MMFIDMASK> symbol expected in GetBaseClass at line" error message by changing the first line of my global config file to

~b 'global'

with single right quotes. This is in an ubuntu environment though and might not help your specific case.

-Eric

--- (Edited on 6/8/2015 1:00 pm [GMT-0500] by Visitor) ---