[direwolf20]

The parser in Z-machine games comes from the game, not from the runtime, so the Z-machine version is completely irrelevant and the only reason porting to Inform 6 would make a difference is that you'd be linking it with a different parser.

[anthk]

Woudn't a Z8 game have an improved parser over a V5 one?

[direwolf20]

No because the parser is part of the game, not the runtime