CS,
I worked with WordPress for many years and have installed at least 50 different themes. Atelier is, by far, the best theme we have worked with to date, and, continues to be improved by the team.
- Does your host fully support WordPress, including latest script updates?
- Did you do a clean install as https?
- Did you set all permalinks?
- Did you install Atelier from Dashboard?
- Did you install more than one Demo?
Although I am an independent developer, it appears to me that the problem is with your installation/configuration, not Atelier/SwiftIdeas.
It sounds as though you need to start over with a clean install and be sure that your host is optimized for WordPress.
Regards,
David