Next press 'Ok' and wait for progressbar. IF YOU HAVE PROBLEM: progressbar freezes on one of frames while assembling animation - may be this frame was drawed not in paintcad of corrupted. To fix it: remember number or frame on which assembling was freezed, restart PaintCAD, launch PaintCAD in 8bpp mode, open GIF (Via 'Open GIF', not 'Open ???') which freezes assembling, and save them with overwriting his old file. Then after it PaintCAD saves already fixed GIF without any errors inside gif-file. Next - repeat call of 'Pack aniGIF' and animation assembling. If freezing will be repeated on one of next frames - repeat procedure of GIF-resaving for other frames which will freeze assembling.