FFCore does not support designation of non-integer values for font sizes.
I think I have found my answer to the Fonts available part of my question. It appears you have to restart the server in ordeer for the Fonts to become available.
What Fonts Can be used for Watermarks and can any be added (I added a font to the server but it did not show up in the list for Watermarks). Also can we use fractional point sizes IE: 6.5 Pt?