Legal Question in Constitutional Law in Florida

No.

Not successfully. Laws change all the time, and the changes usually leave some people worse off than they were before. That is not enough to give those affected a valid claim against anyone.

There is also a separation-of-powers issue here. Whether to enact a new statute is up to the Legislative branch, while whether to sign it is up to the Executive branch. As long as those decisions are constitutional, the Judicial branch has no authority to override them.

Additionally, government officials - including the president -- are not liable for actions they take as part of their duties. There are exceptions to this rule, but none would apply in the situation you describe.

I'm sorry I can't be more encouraging. Good luck.