I’ve encountered the very similar bug described in Metadata is lost when exporting package to nexus and installing it. · Issue #5123 · conan-io/conan · GitHub
I have created a conan package via GitLab CI/CD and everything looks fine. Also header-only packages work. BUT the package files themselves are never offered. Everything looks fine, yet I’m missing the conan_package.tgz file when accessing the digest via the GitLab conan API as depicted in Conan API | GitLab.
And therefore a conan download or conan install fails.