I have created a new Project Template by exporting a project via Project -> Export Template. Opening Visual Studio now, I can see my template showing up.
I then went to
Documents\Visual Studio 2022\My Exported Templates
and moved the MyTemplate.zip to another folder. Went to
Documents\Visual Studio 2022\Templates\ProjectTemplates
and made sure that MyTemplate.zip is not in there as well.
Now when I open VS again, I can see that my template is not available anymore.
To counter check, I moved the zip back into Documents\Visual Studio 2022\Templates\ProjectTemplates , reopened VS and made sure that the template is visible again.
I then went ahead, extracted MyTemplate.zip and compressed it into a zip again (Right Click -> Compress to Zip). Now when I move that zip into Documents\Visual Studio 2022\Templates\ProjectTemplates and restart VS, the template does not show up.
Bottom line, I am unable to import any template that I have manually compressed into a zip archive, seems like something is happening to the zip during extract / compress. I have been testing this on Win 11 with the OOB zip tools as well as nanazip.