Great news!
Last time I forgot to mention one obvious problem: in Dec 1941 scenario (both versions) Japan player starts at war with USA and GB. This is accurate but because USA and GB players play first it is Japan that is being attacked in 1941, not the other way around! I suggest to start them at peace, and then use Python command to force Japan to declare war in BOTH versions. Even in non-permanent war/peace version it can be very annoying for Japanese human player to sit and observe how British Freighters attack Japanese Heavy Cruisers. By the way, can we make Freight defend only units? AI is misusing them anyway, and legitimate freighters usually never attacked in real war.
Somebody named Great Artist -- Rolling Stones

Mick Jagger, anyone? Very appropriately he was born during the war year of 1943, by the way
We also have larger problem of planes not being able to attack ships in port. To test the whole issue I suggest you to recreate the whole Perl Harbor attack. Naval torpedo bombers only end up damaging land units to certain degree, It is currently impossible to sink a ship in port. While we are there -- something really silly happened with the names of all the US ships -- they are named HMS, and not USS. There are no Majesties in America!
Nanjing mistake was not corrected, again, it was captured in 1937, but even in 1941 it still shown as Chinese capital

. Chongqing was a municipality of the Republic of China (ROC) administration, serving as its wartime capital during the Second Sino-Japanese War (1937–1945). Any lack in changing their flag?
I strongly recommend to take a look at
War in Pacific excellent scenario/mode. Very smooth work of art, you may end up playing it for days instead of modding

They have Nationalist Chinese flag and overall accurate initial situation. Even if you don't end up using DCM integrated in that scenario, it still can provide you with valuable pointers.
For some reason Japan starts at war with Iran in 1941.