It's worth noting that, depending on the specific timeframe you're looking at, the KMT was not a cohesive whole and more of a very mixed bag united front against the Qing + (other) warlords + the Japanese + etc. It's essentially what would have happened if Russia went through the February revolution and never had the follow-up October revolution and somehow the White government had survived past a year or two: a complete mess of ideologically incompatible bickering factions who haven't splintered or backstabbed each other yet.

KMT troops were trained by Germans, and received economic aid to barely cling on to power against warlords and bandits in the 30's.

However, Third Reich aid to the KMT government stopped in 1937 after the Japanese invasion and all relations ceased between Nazi Germany and Nationalist China by 1941.

You can read a NATOpedia summary here