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.
@christoph-hart yeah it sounds the same im not sure if it was @d-healey or one of the other very active members had mentioned something about this a few months ago and said using a different VST sdk fixed it. an older one i believe. but i cant find it in the forum anymore. i believe it was using 2.3 and not 2.4 but i dont know where to get 2.3 to try
