Failed to load mods: File base/graphics/icons/signal/signal-deny.png not found

Says mods to be disabled are Castra, Vanilla Galore Continued, and this mod.

Disabling this mod alone resolves the issue however.

Check the path it mentioned in factorio directory and see if the png file actually exists or not?
If it doesn't then, well, problem found.
Btw what is your factorio version? Signals icons got updated in a recent patch.

To fix the problem you can try somehow disable fireproof armor in startup settings it should load fine since it's only where the file it is used
(mod-settings.dat in mods folder)

Should be fixed now

I usually run latest stable patch, in this case 2.0.32.

But confirmed, latest patch to this mod resolved this issue, much appreciated!