I installed the fonts on my Mac and ran into numerous issues.
You apparently built the fonts in FontCreator Project, which I don’t have. However, I opened the VF .ttf files in Glyphs and FontLab, which could have introduced additional problems.
Anyway, the first problem I noticed is that when I installed both the italic and roman font, my Mac told me I had installed duplicate fonts. This made me suspect a naming problem. Upon opening the VF.ttf file in Glyphs, I noticed names of the fonts were all Sans San Mateo, which created the typeface family and is as it should be. However, the italic masters had the same names as the roman masters. The italic masters need to be named differently from the roman — for example BoldItalic and Bold.
In addition, both Glyphs and FontLab told me there were discrepancies between the glyphs in the masters. For example (one of several), in the italic fonts, the E in the light master has an anchor for the descending diacritic combining marks, but the bold master does not. I suspect these sorts of issues exist within the roman fonts too but I didn’t check. These discrepancies interfere with the interpolation of the instances between the two masters.
I also noticed that the character set of the roman VF file is much more extensive than the character set of the italics. I don’t think this would cause the problems I noticed, but the character sets should be the same.
In addition, I couldn’t get the fonts to show up at all in Adobe Illustrator, but they did appear in InDesign. However, some glyphs were missing. For example, InDesign tells me the italics space character is missing (didn’t check the roman). This is weird since the unicode position, 0020, is present in both italic font masters.
These are all things I noticed while trying to install the fonts and subsequently opening the VF.ttf files. As I mentioned, opening the compiled fonts rather than the .fcp files might have introduced problems on its own. Unfortunately, I suspect the fonts contain multiple problems that are showing up in various ways in various software applications.