Ok so i've finally climbed back down into the dark tunnel of the Point Motivator source code to look into this..
There is no super easy fix, but there are a few options to enable this:
1. I could add a global option that says to report points as dollars (or user defined currency), so that instead of the main display saying "300 points" it would say "$3.00"
And then probably make the same change to the charts and summary reports.
But this would leave all of the dialogs and settings exactly as they are, so that when configuring things you would use "100" to mean "$1.00"
2. I could try to more properly convert everything to floating point values.