It's complicated; motion vfx and smoke simulation

Ok, I’m trying to wrap my head around this physics, motion tracking, compositing thing. My problem is wrapping everything up because of… issues. I’ll try to be direct by simply addressing my questions to then get to the final result… Ok, so there are negative key frames on the timeline, but I can’t move anything lower than zero. I have a smoke simulation baked but it isn’t starting before 0, so it doesn’t align with the video for the motion tracked video. SO, I would like to move the video and keys for the motion capture back to align to the smoke, OR move the smoke bake back to align with the video, and as far as I can tell that involves a couple hundred frames of renaming…So, I suppose my question is this; how do I move motion tracked video around and or smoke simulations around so that they align the way I wish?