Yes. If Outlook is properly configured, then you should not have to do anything to tell X1 to use it. You will see that it is there when you "Manage data sources".
Why would you want to put the PST file in a Dropbox folder? These are strange locations that Windows probably treats differently. It is, after all, the local mirror of an on-line (cloud) repository.
If Windows and Office are working just fine with this arrangement, then X1 shouldn't need any intervention on your part.
If that does not work, then I would tell Outlook to put its Mail Profile in a more conventional location.