This is on W10...
The Eclipse IDE is the "general" ("C++") version, not the Rust-specific flavoured IDE. Because I'm mainly using other languages: Python, JS, etc.
I'm able to get the format highlighting for my .rs files (following this previous question and answer).
But I'm completely in the dark about what you're meant to put for Window --> Prefs --> Rust --> "Working directory". This was preset to C:\Desktop, which seemed a bit strange. Whatever I put there seems to raise a "mild" complaint about a missing .toml file.
Surely a .toml file is going to be specific to a given project, rather than generic to the Rust installation itself?
I'm currently mainly running things from the command line rather than from inside Eclipse but I expect that to get the maximum out of Corrosion it's probably best to understand how to configure it properly.