I've done a bit of research on the web and this is where I've gotten to:
While this is badged as a Meng kit, it has its origins with the now defunct Wingnut Wings (WNW).
All the sprues match the test shots displayed at Scale Model World 2019 except for the engine sprue E (https://forum.largescalemodeller.com/topic/8670-meng-132-fokker-dr-i-fi/). I seems that Meng had to develop their own engine sprue.
The sprues include parts for nearly all Dr.Is from the first two pre-production aircraft that saw combat to the final production version, all in the one box. All bar 4 of the parts are featured in the instructions, a third propeller, a mysterious clear part and a second undercarriage wing (2 parts).
From their promotional material, WNW planned to release at least two boxings, Early and Late Dr.Is.
The schemes in the box include the second pre-production aircraft (F.I Nr. 103/17), two early production aircraft (Nr. 202/17 and Nr. 206/17) and one late production aircraft (Nr.425/17).
For the most part the instructions differentiate between each of the versions, however there is at least one error that I have spotted and three steps were it is unclear which version should have what option (or none of them) applied. There is also one difference in the early and late wings that isn't mentioned anywhere. I'm sure WNW knew what they were doing, but they don't seem to have told Meng.
I don't have an useful books in my library to reference, so I have done, and am continuing to do, a bit of research on the internet, which I will document here in the days to come.
Any assistance, questions, observations or corrections will be welcome.