Bug work around! I will repost this as FM12 Network Service. Start circuit normally and wait until upper circuit is running. Pull in bottom primary switch and the circuit will behave normally. Note that unlike a FM2 Service (2 hots 180 degrees out of phase) the neutral always carries current. I realized that you were exactly right about having some resistance in the primary transformer circuit so I added some. You can get the "can't find solution" if you don't because the current is infinite.
I will expand this to full 3 phase circuit with additional second primary switch for FM16 120/208V WYE service. By simply sequencing the primary sources one at a time one can work around this bug without adding too much complexity.
Thank you all for the help with the bug.
