IIRC, the best practices whitepaper / video recommends that your repo be in-place - put it at C:\Program Files\Inductive Automation\Ignition\data\projects
If you put it there then you don't need to import/export or reload or anything. It just works.
There is a bit of a race condition there if the designer is open, which was demonstrated in the video.
There also seems to be a mapping constraint - one gateway per one designer machine. Swapping from gateway to gateway would be a bit odd to me... so I put my repos in the subfolder - one repo per Ignition project. That does cause some duplication of gateway scoped resources but when you choose your solution you also are choosing your problems.
I haven't tried cloning a repo to a clean machine and starting to work on it the way that I would have in other technologies. The designer seems happy if the project is created on disk first and then linked / cloned and the demos follow that path. My guess is that it would be fine.
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