Hello Wilma,
Sorry for the delay. I have not been in the forum for a while. Next time, if you want a faster response, please send a short mail to support@fatpaint.com.
Because Java don't work well on Mac's, to save stuff locally on your pc, you have to do this:
1. Save images or project files online on your Fatpaint storage space.
2. Open the “File manager” from the ”File” menu (at the top). Then in the File Manager, right click with the mouse on the file you want and select “Download to your pc”, or just click on the file you want and select the same action from the “File” menu in the File Manager.
That's it. Hope this helps.