Converted sketchup to .3dm and o snap not working

hi, had a friend export their sketchup file to .3dm format so I could use it in Rhino for mac.
it is a 3d model of battery park city in new york from 3d warehouse
i am trying to get linear dimensions, but the o snap functionality in rhino is not working.
any ideas?

thanks in advance!

That model is most likely a mesh. Make sure to use the Vertex snap.

Thank you! very helpful.
any idea why the linear dimension doesn’t display a number when i pull it out from an edge?

… sorry for the beginning q’s!

That could be several things. Could you post (part of) the file with the dimension?

Have a look at your settings (file menu), under dimensions > text, text size is probably too small to see.