The completely white projectiles can be fixed by not using HDR rendering. Using basic HDR rendering will largely mitigate the issue, so I'd recommend using the high preset instead of ultra if this issue bothers you. Unfortunately, I don't think there's an easy way to fully fix this issue. I wasn't able to replicate the first issue you listed, though I noticed the sun was visible during the Name Deity fight when using HDR rendering and was not visible otherwise. Which graphics API are you using?

Waat i did mean is that when nameless deity spawns the fancy lighting disables automatically and it says on chat that some bug ocurred , also , I found some another glitchs , this time on infernum mod
1 : if you summon DoG in infernum difficulty the game bugs and only shows the background (Even the UI disappears)
2 : Ceaseless void and poltherghast slow down the game to 50% speed for unknow reason
also , Ho i know what is my graphics API?

forgot to mention that infernum ares laser causes slowdown too
i dont know why that slowdown with these specific bosses happens , my pc is very good and im not using much mods

Could you please post the error from the chat? I have not experienced any issues like that.

Shortly after you launch tModLoader, there should be a line in the terminal window containing "FNA3D Driver: " (without quotes), and the graphics driver should be listed afterward. IIRC, it should be either D3D11, OpenGL, or Vulkan. If you are on Windows it will most likely be D3D11.

I will take a look at your other issues a bit later.

I was able to reproduce the issue with the DoG, but was unable to reproduce the other issues.

A partial fix for the DoG sky bug is coming in the next update. The bug will no longer occur, but HDR rendering will not work while fighting DoG. I don't know what exactly is causing this bug, but I suspect the Infernum mod is doing something unusual.

The fancy lightning is not being disabled anymore during nameless fight for some reason , But some effects like the tree on the garden that has a red aura is a bit buggy , my graphics api is indeed D3D11 , i dont know what setting makes infernum polt and cease lag but when i put the default settings (low) and enable HDR render manually it wont lag (I use HDR especially for Bloom and sprite lightning , it makes everything beautiful) , maybe it lags bacuse of some High or ultra config.