Superpolator is part of a UFO based workflow. UFO can be exported and imported with FontLab Studio, RoboFab Scripting, RoboFog and FontForge.
Superpolator uses and generates UFO based font sources. Class kerning can be interpolated, but masters need the same group definitions. Superpolator does not read or interpret OpenType feature files.
A windows version is not planned. The code-only Superpolator library, (the underlying toolkit, everything but the interface) is a platform independent Python pacakge and can be licensed for other tools using Superpolation-style interpolation.
Superpolator does not magically draw new masters for you. It can extrapolate very cleverly and allows you to explore all corners of the designspace marked out by your drawings. But you always have to generate and correct the contours.
The app does not make the glyphs interpolatable, the masters need to have the right number of contours in the right order, each contour the right number of on-curve points. You know the drill. Ask TypeSupply about their Prepolator application.
Neither is Superpolator the only way to interpolate type. Most font editors have one way or another to interpolate two fonts and make a third. The reason Superpolator was written is that this is no longer enough. Contemporary typeface families usually have two or more axes, bunches of masters and typedesigners have to develop very complicated methods to build them. FontLab’s interpolation tools are based on Adobe’s Multiple Master technology. A breakthrough in 1993, but restricting and limiting today. Superpolator remedies that by introducing a flexible way to build interpolation systems. The tool has to accomodate the typeface, not the other way round.