-Obligatory notice that the below is not legal advice from a lawyer, just friendly tips to research-
Tell your friend to go to try going to the state bar association. The state bar association handles most cases against lawyers for malpractice, and they may be able to refer her to a new lawyer to take her case (maybe even pro bono). Finding a new attorney sucks, but it may be necessary for her to solve the problems caused by her relationship with her current lawyer. Sometimes terminating a lawyer-client relationship close to the trial date can be a breach of ethics. Therefore, your friend may have a malpractice case against her current lawyer. Additionally, her new attorney may want to look into asking for a continuance from the court given her current lawyer's behavior.
Also, your friend's retainer should be held in a trust account separate from the active accounts for the law firm - this is a very important state bar requirement. An attorney should only withdraw funds from the trust account after performing services, usually this procedure is detailed in an invoice/statement sent to the client. So, your friend may have received an invoice if her current lawyer has drawn funds from the retainer for services rendered. Any amount remaining in the retainer should be safe in the trust account. The state bar association and/or your friend's new attorney should be able to advise her on the correct procedure for recovering her retainer if there are any issues.
If I was your friend, I would consult my new attorney on how to proceed in recovering the retainer and any work product from the current lawyer. Your friend can ask her current lawyer directly to turn over the retainer and any work product produced immediately; however, the new attorney may be helpful to avoid/overcome any issues.
Best of luck.