If you start with one of the FMP 14 starter solutions or a brand new file of your own creation, do you get this same crash when opening the workspace?
Got any plug ins from previous versions installed? (If so, remove them and try again.)
If a brand new file has the same issue and you have no installed plug ins, then you may need to uninstall and re-install FMP 14.
You may also want to call FileMaker Tech support. They do not charge for "installation issues" and this would appear to be one.