A: Absolutely. It's important to be represented by someone you're comfortable with and can trust. You can either have your new attorney get the file from your old attorney, or get it yourself and forward it on.
A: There ARE circumstances where the fee can go up in a mass tort case, but you would have been notified and signed a joint representation agreement at the start. The fee should total 40% + costs for cases in litigation, give or take. The fee doesn't go up just because another lawyer is involved - the lawyers split the fee among themselves.
That being said, it's totally normal for a firm to associate in a 2nd law firm who already has a bunch of the particular bad drug cases.
A: The standard fee for personal injury cases, including sex abuse cases, is 1/3 of the total recovery plus costs advanced. If the matter goes to litigation, the fee goes up to 40% plus costs advanced.
I commend your bravery in coming forward to get some justice. I wish you the best.