I think I found another minor bug. It's hard to tell for sure, but this is how it looks to me. When you set frame interpolation to 1, the empeg uses that as 1 frame of interpolation between the two key frames. On the editor's preview, it seems to be off by one so that 1 and 0 have the same effect of no frames inbetween the key frames.

Maybe it's just my eyes going buggy, but that's how it looks to me.