Building crossovers with the Fast Tracks jigs requires a certain order of operations.
I build each component turnout of the crossover, using the outside (non-frog connected) stock rail and points first. Then I will install the frog, of which, one leg of is the stock rail for the other turnout in the pair.
Once you have that, you can square the turnouts up, notch the stock rail (if you didn't measure it correctly first OR if you haven't notched it already) for the points and then finish your soldering job.
During the build, I realized that I had to build the LH crossover with a RH turnout immediately following the crossover to get to the Amtrak station. My first set of partials didn't have a long enough stock rail.
Oops.
I had to recut points and frogs and restart the build.
Building complex trackwork like this will make you wish you could buy ME rail in lengths longer than 3'; I could use 6' or longer pieces without issue.