Can you please expand on the question a bit? It would help if you could sketch out a very simple example example with maybe just 2-3 states in chart1 and the corresponding transitions required in chart2.
Something which might work (without knowing exactly what the problem is) is "Inner transitions". One place where you do get a lot of transitions is a situation where whenever some condition is true, you want to transition to a given state irrespective of where you are. In this case, suppose you have N states each with a condition [ci] for transitioning to it, you will need N^2 transitions to spell out the behavior correctly.
To avoid this, you can use inner transitions. This reduces you to only need N inner transitions rather than N^2 outer transitions.
This is probably best explained using a sketch but unfortunately I do not know of a way to attach an image.