Found this via another forum:
http://www.machsupport.com/docs/Mach3_CVSettings_v2.pdf

It recommends enabling CV and disabling all CV settings until more familiar with the system and its interactions.

Thanks again for your help in solving this issue.

No probs
Hood

I would take that doc with a pinch of salt. As I've said in many threads - it's not very good and in some places just plain wrong.

Your original CV Distance of 1.0 means you're allowing (not telling) CV to drop to 1 unit/min if it needs to which is (as you've found on your machine) just about the same as exact stop. Setting this to your commanded feedrate is pointless - CV can't do that by it's very nature.

Ian