CP8 - trying to launch a pdf from a subfolder on a button - not working - any suggestions?

Tryong to open a pdf from a folder /pdf/documentname.pdf - using the action Open URL or File - deselected "continue playing project" - works if file is in same folder as published content - need to keep sepearet for security access reasons

saw this was a bug in CP7 - I am using CP8 - anyone???