Retina output on a Mac

[Andrew Henshaw]

Apart from compiling with 6.6.2+,  is there anything else I need to set to enable retina output on a mac?

I dont have retina on my mac,  so I used air display and my iPad to test the retina output and that just worked,  when I dragged the window onto the iPad retina display is just redrew ans became super sharp.

I ask because I have a user that says one of my apps is not displaying as retina,  and has sent me a screen shot where everything looks scaled.

Ive changed all the graphics in the app so they are read from a folder,  and there are both standard and retina versions of the images in the folder.  Is there anything else ive overlooked?