The regulators are a known issue. The cables eventually stretch and the windows won't drop. There is a bike cable adjuster hack to buy time. In the end, the regulators need to be replaced. Switches could be an issue. Start by reading through this article. It should get you going in the right direction.
https://www.pelicanparts.com/techarticles/Boxster_Tech/77-BODY-Window_Regulator/77-BODY-Window_Regulator.htm