Dat zijn rare foutmeldingen. Probeer inderdaad eerst de andere packages opnieuw te installeren.
Als dat niet helpt kan ik je mijn kopie van RF sturen, die werkt prima onder FontLab 5.1.4 (4868) en Yosemite.
Based on my own findings when making pixel typefaces in the 1990s I found that serifs require a certain fidelity from the medium in which they are rendered in order to improve readability. On a grid of anything between 9 and approx. 20 ppem serifs are usually just heavy slabs that clutter shapes, and make good spacing more difficult. In these environments a pixel more or less can make a huge difference.
I was curious if the addition of serifs would enhance the legibility of my typeface. In traditional type design the role of serifs is to emphasize the horizontals and to optically ‘glue’ letters together within a word. I was looking for ways to achieve this effect in my design but discovered that the addition of horizontal serifs was not the solution. Some letters started to physically touch each other (like the rm combination for instance). The spacing between the letters altered dramatically as well. In my opinion it became too tight.
And then there was RoboFog, a customised version of Fontograper 3.5 modified by Petr van Blokland, Just van Rossum and Erik van Blokland in 1995, that was the first font editor to include Python scripting. This introduced many type designers at that time to Python.