Latest version of Rhino erased my work

I was working with the latest version of Rhino 5 for Mac (can’t remember from which date was), finished all my work and saved it. Later that day a new version came up and installed it (version from the 18th Nov.) Today I opened the file and some parts of my design were missing! The part that went missing was one of the first things I modelled in the file, there are newer things I built still in there.
Is there a way to make them come back?!
Not new in Rhino, but not a pro…help!

Hi Karina - Are there any hidden objects or ‘off’ layers?

-Pascal

No, already checked that a thousand times! I’m guessing it happened when I installed the new version, but don’t know why…

maybe try another view style setting? for instance, lines won’t appear in rendered view by default.
switch to shaded etc.
?

No…checked all that.
Had a long night yesterday doing it all over again…thanks anyway!