Platformer Gravity doesn't currently work with 3.2, but the warnings on the other two plugins won't cause any problems and should go away after the first successful build. You can also find the older version of GBStudio here: https://github.com/chrismaltby/gb-studio/releases/tag/v3.1.0
I've been doing some updates to try and get a fully compatible version working for GBstudio 4.0 when that comes out of Beta.