Snagit Serial numbers and management features are all applied at install time using an MST. However, your install uses *.EXE files. Could you please publish an MSI version with MST support?
We are investigating this as an install method. Please see https://ideas.patchmypc.com/ideas/PATCHMYPC-I-204. Thanks!
Ahhh. Thanks Andrew. I threw my name on the ticket :-)