Ghost Objects in 2015 Pro

[orchard collie]

Hi from Darwin Australia
Help Wanted!
Just loaded 2015 yesterday on my MacBook Pro (OSX 10.8.5). Have suddenly encountered ghost or phantom copies of groups in my model. No lines, just surfaces. Can't select it with pick arrow and Command-A doesn't work either. Anyone got any ideas as to how this can be fixed or do I have to go back to 2014 which never did this to me?
Tried turning off Hardware acceleration but that didn't fix it, any other thoughts.
Orchard Collie

[pbacot]

This happens to me when I have more than one large SU file open (in SU 8). I don't know the cause but it goes away if I reopen the file.

[orchard collie]

Thanks
Did just that and it went away
Yeah Team
Cheers