Can I copy objects from MotionGIF file A to file B?

Yes. In just two steps, 1. In MotionGIF file A, select the objects you need to copy (hold down Ctrl for multi-selection), and press Ctrl+C, or choose Copy from the Edit menu. 2. Open file B by clicking the Open button on the toolbar or choose Open... from the File menu. Go to the frame you want to have the objects copied, and press Ctrl+V. Or choose Paste from the Edit menu.