using Regex in Application control rules

I have not been able to find any guides or examples of using the regular expression in the Process Definition panel for Application Control.  I have checked my regex on regex101.com and regerx.com and the regex works correctly in those tools.  When I do an exact match in the rule, it  blocks just fine.  But the regex rule never triggers or logs anything.  Any suggestions on examples of regex in application control or how to troubleshoot regex in application control?