I have made a public repository for various fasmg macros:
https://github.com/tgrysztar/fasmg

At the moment it just contains various macros I have made, including the fasm-compatible Windows headers. But the choice of GitHub reveals my hope that other creators may join in the future, perhaps adding other sets of macros, architectures, etc.

Even if I remain alone there, I may continue using this repository to maintain the Windows headers project. But if anyone would like to join and work on the macro packages, please feel invited.

Though I also keep in mind that the past attempts at doing something similar for fasm 1 have more or less failed in the end.

i can revive it, and put missing parameters count, api functions, and structures. (because i like fasm 1)

question:
does this mean fasm 1 will be discontinued?

fasmg does not completely replace fasm 1, that would be the role of fasm 2 - which may one day be made, based on fasmg engine, but may as well never be - and therefore fasm 1 remains supported, even if not much is happening there.

"but may as well never be - and therefore fasm 1 remains supported"
hope so, thanks.