There are no know issues related to Mojave (unless you are using the 3.1 beta). Could you please email support (mac.support AT literatureandlatte.com) so that we can help?
One thing to try in the meantime is to hold down Shift as you launch Scrivener. This will cause it to open but not to open any projects. If that works, try opening a project, and see if the crash only occurs with a specific project. That will give us something more to go on. I'm sure we'll be able to get you up and running soon.
All the best, Keith
"You can't waltz in here, use my toaster, and start spouting universal truths without qualification."