You Suck At Parking is a clever driving puzzle game where you have to overcome obstacles in order to park your vehicles. Sound simple? No... its not! Fly over jumps, launch through explosive thrusters, fight against huge fans and get lost in the deep water. Everything rendered in beautiful island-esque cartoon world with perfect physics for your entertainment and frustration. Failing is an option, then you can just give it another go!

https://store.steampowered.com/app/837880/You_Suck_at_Parking/



You Suck At Parking demo runs fine in Proton until you load the menu or another level. Its seriously an issue with Proton and Unity 3D or Unreal Engine games. I've never had this problem until recently yet all of my other Wine games and native games run fine! I recently posted GOG's Wolfenstein New Order and it runs perfectly!
But most indie games are made in the previously mentioned engines and now I'm having issues...

Here is a post on Reddit about it in detail:
https://www.reddit.com/r/SteamPlay/comments/pcvx40/unrealmade_indie_games_low_performance/

I have found a few workarounds...

• Restart the game
• Force DirectX 10 or 11 in launch options

Launch Options for Steam

Force DirectX 10

• PROTON_USE_WINED3D10=1 %command%

Force DirectX 11

• PROTON_USE_WINED3D11=1 %command%

Specs:
Mint 20.1 64-bit
GeForce GTX 1060
Nvidia 470
Proton 6.3-5