It does get easier once you learn the flow.
Each tool path should be saved as a separate file (Aspire/Vcarve does support tool changing and 1 file for multiple toolpaths but the Xcarve does not so pretend it doesn’t). You’ll save each path using one of the post processors that Larry linked to. Then, in UGS, you will load the file for tool path #1, load the bit and zero for it. Then you’ll run the first toolpath. You’ll swap the bits, re-zero with the new bit and then load and send the file for tool path #2.
I’ve got one design that has 5 toolpaths using 4 different bits and it’s no problem.