Indeed. It doesn't create smooth screenshots, though
The only way to have high framerate is to slow down the Nspire emu a lot, capture at the default speed then use a video program (VirtualDub, for example) that supports GIF and edit the screenshot in there. But then you get an AVI file. Alternatively you can set the final screenshot to be faster than the speed at which it was captured, so it can make it smooth without using a video. Keep in mind Nspire screenshots are really massive, though. About 30 seconds of capture is 5 MB, I think.