Thank you for the investigation and the additional details 
At the moment it looks like this is related to the font file structure the font designers are using to code information inside the font files themselves. We are working on removing this limitation as it does indeed prevent FontBase from parsing/loading certain font files. Unfortunately at the moment these is no immediate solution to this situation, it is still a work in progress.
As for installing font files into the Fonts folder and them then not showing up in FontBase - that is not really a bug. I understand this might sound counter-intuitive, sorry about that. Here is a bit information on one time we investigated this particular behaviour:
Thank you again,