I have the same issue. If I add the files from part 2 into part 1 I get an error that it failed to load the archive. If I do the inverse, I get the same error. If it can be downloaded as an unbroken download there isn't an issue, such as if I download from DLsite, which I can't read any of the text then. But combining 2 archives together makes it so the game fails to launch.
Viewing post in Axe Maiden Vana v1.00 (Public Build) comments
Hmm, Okay I uploaded a version that has not been separated into parts here: https://easyupload.io/ykmdq9
Please let me know if this version plays for you.