Knowledge studio Pre-annotation on Regex
It used to work very well but somehow the Regex rules no longer apply to my documents after running pre-annotation. I defined Entity/Rule Money and Percent. Below is what I have: 
I have linked the Money rule and Percent Rule in pre-annotator 
After executed pre-annotation by clicking "Apply This Pre-Annotator", I get all other entities annotated, except for Money and Percent.
Appreciate your help to clarify how should I apply the regex.
It seems that there are some mix-up. To use the regexp rules as pre-annotator, you need to perform Pre-annotating documents with the rule-based model steps. https://console.bluemix.net/docs/services/watson-knowledge-studio/preannotation.html#wks_preannotrule
However, the 2nd and 3rd screen shots above shows configurations for dictionary so I would assume you ran dictionary-based pre-annotator instead of the rule-based pre-annotator.