Hello all,
First post... I contact LEGO about this a while back, they gave me a work around and said they were fixing the issue. It worked for a while, then I had the same issue, repeatedly. Yesterday I installed another Yosemite update and LDD is working again. I don't know if they're connected or if it will stay fixed. Anyway, the temporary fix provided by LEGO was:
Thanks for getting in touch with us.
We are sorry to hear that your LEGO® Digital Design software is having problems with saving. The LDD software engineers are trying to fix the issue but in the meantime we have a workaround for you.
What to do: ( manual editing of: "/Applications/LEGODigitalDesigner.app/Contents/Info.plist" )
-make sure you have admin rights to your PC
-right click on the "LEGO Digital Designer" icon
-choose "Show Package Contents"
-The Finder will then open a window with the "Contents" folder
-double click on "Info.plist".
-delete these lines: <key>LSMinimumSystemVersion</key> <string>10.4.11</string>
This work around should fix the situation for you. We want you to enjoy the program to its fullest and we understand that saving is a big part of that. We hope to hear that this has fixed everything up for you and you can make some amazingly creative designs.