[FeuerSturm]

the plugin auto-creates a file called "particledefault.vmt" in
"/orangebox/dod/materials/particle/" which is needed to color
the blood and display it correctly.

Players will automatically download it when they connect to your
server (if they allow custom content, if not they will see the purple squares).

So if you use FastDownloading you will need to upload that file
with the correct folder structure to your webhost as well.

After that it should work fine