"4 Hong Kong v1.3.1" played with v5.2.9
(EDIT: Now I see it may have been the v5.3.0 instead, don't know)
Small notice: I've played this one out of my mod, but it shouldn't matter much, as it's helping only the Japanese in this scenario, so at the most, it's more challenging for me. (And I didn't take the Vicker's tank)
Like with your previous scenarios, it's kind of always playing out the same way for me: A very good challenge at first, with an optimal unit/RP balance to not allow many mistakes. But in the end I'll always end up with way too many units and just overrunning the enemy. Like in this one: I wouldn't have needed both of the final reinforcement waves. Good action otherwise.
I suspect, that "breaking" the supply connection (sec. obj) should have resulted in an immediate defeat to the player (?)
First, this doesn't happen: one can continue playing, but to no avail, as one of the primary objectives' marked "failed", allowing a draw at best. So second, you may want to correct it and change it to a primary objective at the same time. How about switching it with the "fight off the Jap. attack" prim. objective? Holding the towns and preventing Hong Kong's encirclement are the main objectives, right? So finishing off the Japs can be considered a "bonus" objective for an early victory condition.

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suggestions
- I've been able to destroy the Jap supply ships of the eastern attack wing quite early on (with the cruiser and plane), making the whole flank and the arriving reinforcements quite useless once this happended. Maybe add some additional supply ships for each invasion wave.
- and Spike was right about way too many AI controlled units at the start. I didn't mind the AI taking over the Brit ground forces - although behaving quite stupid, like attacking a high star enemy infantry with the AT gun! But it really was quite tiresome to watch the
lengthy naval battles fought between "my" and the "enemy's" AI - resulting in literally nothing: no pain, no gain. The only thing I
really wanted the AI units to do was to attack the Jap supply ships, and that they
did not.
- don't know if intended, but the Jap air force was undersupplied from the start
- you should move the Brit AA unit one hex to include the airfield from the beginning!
- I know it's only for the looks, but you should include at least some pics to the events. Please, looks a bit bland like this.

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A nice defensive mission, I liked it. Thanks, Duplex!

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