AWS Marketplace GitLab CE problem

So wanting to test out Gitlab for potential self-hosting at work I installed the CE build on AWS:
It’s version 11.10.4 btw and a vanilla install, followed the instructions all good.

While the webUI is all great and I can create projects, manage users, keys etc, I can’t seem to be able to actually connect and push/pull/commit to those repos. I have set up SSH keys and can ssh into the instance for my ssh: ‘Welcome to GitLab, @lostsheep007!’ message but when I then attempt to actually do something I get:

‘connect to host port 22: Operation timed out
fatal: Could not read from remote repository.
Please make sure you have the correct access rights and the repository exists.’

The repo exists, so is it the access? Yet the AWS security group I defined as instructed is wide open on port 22. Same problem on public and private repos.

What have I overlooked?

Did you have a look at /var/log/gitlab/sshd/current and /var/log/gitlab/gitlab-shell/gitlab-shell.log for any evidence of what is going on ?