MW 1.20.x doesn't have the ApiQueryORM class.
Users can only download the git master version of UW at
and the extension distributor at
just offers 1.19x as default choice, but then fails saying "Invalid response from Extension Distributor remote client."
The UploadWizard git repo has no tag for MW 1.20.x.
Hence users can only download the git master UW. That, however, requires the ApiQueryORM class to be present. Therefore it doesn't work with a vanilla MW 1.20.x install.
MW 1.20.x is, at the time of this writing, the latest stable version.
So please, either
- fix this such that people can download somewhere a version of UploadWizard that is compatible with MW 1.20, or
- make sure that git master remains compatible with the latest stable release, or
- find some other simple solution such that people can use UW with MW 1.20.x.