Word Perfect Greek Module

Help!  I've recently installed this module on a stand-alone CompuAdd 425, 
using WP 5.1.  All is fine except I cannot determine how to insert 
combination diacritical marks, i.e., smooth breathing + acute accent, rough 
breathing + acute accent, or circumflex + smooth breathing.  Any assistance 
would be most appreciated.
Barry R. Sang
Associate Professor of Religion
Catawba College  Salisbury,NC  28144