In some rare cases, Mac-based Vectorworks 2018 users are finding that the application takes a long time (i.e. a few minutes) to start up when it's launched.
While we have not been able to recreate this in-house, and we've only heard a few reports of this, we have heard that this suggestion has solved it for most people:
1) Ensure that your Vectorworks installation is up-to-date.
2) Quit Vectorworks.
3) Delete the Resource manager's cache files located here:
/Users/[user]/Library/Application Support/Vectorworks RMCache/rm2018/rmanager_cache.db
4) Restart Vectorworks