OK, I've done a bunch of reading this PM and have learned a lot regarding Magnitude scales. Scales since ML are extensions of ML, and in each's range of validity, each scale is equivalent to the Richter magnitude.

http://earthquake.usgs.gov/learning/faq.php?categoryID=2&faqID=112

Soooo, It is now much simplified now that I understand it better. Magnitude is M regardless of which method is used to calculate it.

Fields:
1. Lower range pull down menu 0.0-9.9 inclusive
2. Upper range pull down menu 0.0-9.9 inclusive

Rules:
1. Upper mag range must be equal to, or greater than, lower mag range.

Pretty simple. Thoughts?