Information about file downloads can be found on page 88 of our user manual. You can try again according to the download steps described in the user manual.
For the problem with the checksum file, I think it may be the case that when you modify the project file and generate the configuration file, you only replace one file instead of a whole file, which will cause the checksum to be wrong.
https://www.stoneitech.com/media/upload/LargeFile/TOOL2019-User-Development-Guide-200327.pdf