I bought this mostly for the ripping functionality but making textures seamless is also a nice bonus however it's quite confusing to work with. The controls are quite strange, having to hold shift just to move textures around and resizing by scrolling is also a weird choice. I'd rather have it behave like any other image editing software where you got a frame with multiple control points to resize and also rotate textures which would also allow to change the aspect ratio of textures. Another thing, and that might just be a me thing, but it's unlcear to me wheter the checkboxes are checked or unchecked it also seems like horizontal and vertical are switched? And i don't really get what the texture atlas size does because it still exports at anything but 256px and when working with textures i'd like them to be a perfect square. Right now it seems like you can place the textures however you want without any real atlas border.
All in all i think this is a great tool to extract textures from pictures that has great potential to be more. Seeing the result of a rip in realtime makes it easy to check if textures line up which i appreciate alot. However there are still some issues and bugs which I hope will be resolved in future updates!