@Christoph-Hart thanks - Yes the politics is pretty stinky.... hey ho...

I think instead of using AUDIO_FILES you should use the {PROJECT_FOLDER} wildcard like with sample maps. That may resolve the / \ issue too. I don't have a suitable project setup to test this so let me know if it solves it.

Go to the export menu and select Export as Instrument. I'm assuming you've already compiled HISE from source before and therefore have everything setup to export.