Loose ball plays and penalties..help :)

[footballref]

Can you guys help me out here. For some reason I have totally confused myself about loose ball plays and penalties. Can you guys lead me in the right direction on these.

Seems like every time I start to think I get a good grasp I do something and totally confuse myself.

Can anyone simplify #1 - loose ball plays #2 - penalties associated to loose ball plays.

Thanks!

Edit ------

One thing confusing me is 2-33-1d: A loose ball play is action during (d) the run or runs which precedes such legal or illegal kick, legal forward pass, backward pass or fumble

The run leading up to a fumble is what is confusing me....I think.

Here is a scenario:

1st & 10 A from the 50. Handoff to A34. A34 runs to B30 where he is hit and fumbles. During the fumble, B55 hits A13 in the back. B12 then recovers the ball at the B28.

I am pretty sure in this situation, that A will accept the hit in the back and go 10 yards from the spot of the fumble (1st & 10 for a from B20).

What am I missing? Why am I confused so bad by this? Am I the only one?