I do not see any profiles that you manage. So you haven't created any yet. Please read up on the one tree phylosophy and the reason that there can only be one profile per person. Meaning that once you have created a wiki profile for someone, it cannot be deleted. Also, you do not have your tree, but you create links between profiles.
Your greeters have left messages with the relevant links.
You can upload and match as many gedcoms as you like. You will only create profiles once you hit the Add button. If you do not see those, you have not completed the matching system.