Fix ranking system

So far so good. Entertaining, good graphics. But the ranking system makes no sense. I get three stars after trying two o more times to complete a level, or just one star when completing a level in only one try. No reason to go back to improve a ranking. Developer needs to explain the rationale for this ranking or improved it.
Well, like everybody else, Im stuck in level 9 industrial era and 7 far west because bugs makes them unresolvable, so I cant play any further. I think to pay for a game you cant play is called scam. Downgraded to one star until it is fixed.

Gandalf5011 about Train Crisis Plus