Aleina Show

Hello! Help me please! I have 2 questions for which I could not find answers. 1) There is a footage in the slide that I want to use as a mask. The duration of the footage is 2 seconds, I need to loop its playback for 15 seconds. Is there any way to do this? 2) I collect a frame from several images. For example, a spruce branch and a toy. I am trying to give the overall movement to the frame using modifiers. So that the branch and the toy swing together. I am unable to adjust the center of rotation of the frame. I use the parameter of the center of rotation in the modifiers panel. I set the value to 100 or -100 along the X axis, the result is the same.