If the Japan player does J1 and pulls it off then by J4 they out spend the allies combined…after that its all down hill for the allies. The allies have no stratgies that work at this point and America can’t build a fleet that can’t be beaten sorry.
Movement is counted every time a unit crosses a border. Land to land, land to sea zone or seazone to seazone.
Formosa-Z20-Z36-Z37-siam is 4 moves as it crosses the borders between (1) formosa and SZ20, (2) SZ20 to SZ36, (3) SZ36 to SZ 37 and finally (4) SZ37 to Siam.
If you move a plane through a seazone that includes an island you are not obligated to cross the island border unless you’re landing there or attacking there. Otherwise you just move through the seazone and ignore the island.