When I make a reference to any of the static files (.js or .css), I'm getting a 500 error. All of the files in question were compiled/generated using pre-compilers/build tools (e.g. Gulp). I don't see any reason why this should cause a problem, but my main suspicion is that there's something about the file's "modified" timestamp that isn't meshing with Sitefinity.
Has anyone encountered similar issues? Any suggestions for resolution?