Distance does magnify issues, but if you don't know what those issues are, you aren't going to solve them. When you can shoot a nice tight group in close, then start moving out slowly. Its tempting to ty to make big jumps in distance, but it can be a waste of time and ammo
Yeah, pre and post ignition push is a bitch. Get it right and its awesome, get it wrong and you get a nice flinch.
It's one of the reasons, snap cap and dummy drills don't work. They can distinguish between the pre or post ignition.
Glad you got a lesson and from a GM.