Hi Mike,
Please ensure there are no errors in the previous screens of data you might have entered specifically check if you have invited participants on the suppliers screen and have added at least one sample content.
Once you resolve all errors that show up once you reach the Summary tab, you should see the "Publish" button activated. If you are not able to find the errors please share screenshot of each screen Rules, Team, Suppliers, Content and complete summary so that specific information instructions can be given.
Cheers!!
Vilas