Save greyed out with Mac build

[Stephen King]

Hi 

I am sure this is a very simple one….

I normally build only for windows and have an application in Livecode 5 (and previously in 4) that builds to an executable (via splash screen) and saves a datafile to the the user documents folder. This has always worked with no problems.

I have recently bought a macbook air running mountain lion. using the same live code file and building for mac, the application runs fine until I try to save. Then the file bane and paths are greyed out and I cannot save.

Are there any switches I need to set to allow saving on the mac?

Cheers
Steve