Cirom
Queen Slime
Thanks for doing that, I am lost in the back and forth between versions and stuff, it is the first time I'm using Github. Anyway, the rainbow-colored 0.png is faulty so just delete it, copy any other color icon and rename it as 0.png. Of course the VipixToolBox folder should be placed in "Modloader/Mod sources", click Build+Reload, and tmodloaderserver should not have the error message.
I did that, replacing it with 29.png, as you expected it to be black. Still getting the error after building, unfortunately. :c