I took a look at the wiring diagrams on the 15 and the 10 which are basically the same as far as LV is concerned .
If you have cross checked all the wiring then I have to believe that you have everything connected properly.
In all of the components you replaced you didn't mention the element contactor. I'm wondering if you disconnected the wires going to the coil of that and then put everything else back the way you said , if it would blow the fuse.
if it does then we at least know that it is not a contactor problem, from there it's a matter of wringing out the wires, basically removing devices until you find what is causing the problem.
The xrmr you replaced has the same or higher VA rating as the original one ?
I'm sure it does , just asking to make sure.
Sorry I can't be of more help but this problem is hard to detect if therre isn't any miswiring involved. It's just a matter of tracing down the components and wiring, Go to the biggest components first, the element contactor probably has the highest low voltage load so I would start there.