Doesn’t Work At All - Will Not Render Video as GIF

Bought this app because it was supposed to be able to convert video files to GIF. I can see the frames of my video in the app. I can see and change all the features of supposed output. But each time I go to save as a GIF, it tells me it cannot find whatever the last frame is of that particular video. Someone clearly put a lot of love into making this app, but it’s going to need a lot more love before it is usable.

Toasted-Ravioli about GIF Brewery 3 by Gfycat