How to change frame attribute for fig element in FM12

[KateColours]

Which files do I use to change frame="all" to frame="none" for the fig element?  And where are the files located?

• I'm using FrameMaker 12 (Technical Communication Suite 5)
• with product interface setting FrameMaker XML Author
• and DITA Version DITAv1.2
• to create Topic, Concept, Task, and Reference files.  

There are 54 "rules.txt" files in the FM program folder - which one(s) do I need to change? I found a similar 2008 question/answer but it addressed Structured FM8.

Thank you very much!