Am i correct in my understanding that you can’t add existing gitlab projects to a gitlab group? the import function failed with some weird error, but that’s beside the point.
the documentation shows two ways to add projects to a group, and both of them are for new projects, not existing projects.
feels inherently non-agile to me.
Hi @nthali, you can indeed add existing GitLab projects to groups by transferring your project to a group. 
Only project owners can transfer a project to a group. They also need to be at least a Maintainer of the target group. Here is a link to the documentation with a step-by-step explanation: Project settings | GitLab
On a side note, do you have a screenshot of the error or what kind of error occurred? 
Thank you! That did the trick, Much appreciated.
Would be really useful to link to the ‘transfer project’ in groups so the option is more easily visible.