I found the offset glitch. you move the "DrawingCanvas" to the upper left (0,0) where the canvas obviously grabs the image, but you didn't move the "DrawingBlob"
I added the following two lines to the start of event 2s actions:
DrawingBlob | Set X to DrawingBlob.X-50
DrawingBlob | Set Y to DrawingBlob.Y-50
(then I put it back after with +50s)
Putting them all in a family and moving them all at once might work too.