If you feel you have enough evidence and want to take it to a small claims then do it. It would mean taking time off work to argue it out in a courtroom - thats if she bothers to shows up.
Even if the judge rules in your favour, it doesn't mean you will see a dime and probably never will...she will have had a judgement against her...sadly...it means squat to many people.
She clearly isn't professional and I hate to say this but based on what I read in your post, you should have paid close attention...actions speak louder than words. My red button alert went off when I read she didn't have a car - pretty much anything - but she wanted to make a movie at everyone elses expense. Sorry, but if someone who wants to make a movie doesn't at the very least have their own transport - thats a bit odd - even if they live in downtown Manhattan.
People are big time users out there. That was her intention all along. She figured she would sucker whoever she could into giving their time and effort away for her. When she found a 'friend' to finish the job, she was finished with you because she knew you would probably persue her further for money in some fashion. She had no intention of paying you so she had to disgard you.
Perhaps politics is a line of work she should consider.
Either way, more of your time will be spent filing a suit against her. Sometimes it makes you feel better to do so...let them know they cannot use and abuse you. No matter what, it is almost 100% guarentee that the girl wont pay a dime.
I took someone to court one time. I took a day off work and had all my paperwork. The defendant never showed up and I won...not by default but by evidence. The defendant could have filed an appeal and I would have had to go back to court and re prove my case. In this case they did not. I never got a dime from them. Nothing ever happened after that.
I often wonder if you take a case to court and win...and no payments are made...you could sell that claim to a collection agency and let them deal with it..maybe show up on their credit report...don't know about that.
Next time...listen to your gut..I will bet you a dollar to a donut that something in your gut was telling you 'something aint right about this...'