This is just a thought but it might push you in the right direction. It is possible that you might have some teeth stripped off of you timing belt. This happened to my brother's girlfriend recently. If some of the teeth stripped off or the gears just jumped a few teeth then the the engine would probably run but it would buck and kick like you describe. This would also account for the weird compression readings you are getting due to the fact that some of the valves may be partially open or closed when the cylinders reach the top of the stroke. I would suspect that hooking a timing light would show you if this is the problem. I'm basing this "diagnostic nugget" on the fact that the crank dictates piston placement and the camshaft controls valves and rotor cap angles. If the belt has slipped then TDC and FIRE don't happen at the same time. (for the sake of this discussion I'm pretending that fire and TDC happen at the same time although it's usually about 5 to 10 degrees apart). I would suspect that anything greater than 15 or 20 degrees would indicate that you have located the problem.

Like I said, It's just a thought. It might be cheaper than a replacement engine but belt replacement can be a big frustration too.

I hope this is of some help.

Dan