Gallery Theme - Exhibitions

I am using the gallery theme on a sub blog. Having set up two exhibitions I cannot find them and end up getting a "Sorry, we can't find the content you are looking for at this URL."

Not sure if I should be setting something else up before creating a gallery. One thing which looks odd is the code which gets inserted into the post. One merely says

[gallery orderby="title"] the other

[gallery link="file" orderby="title"]

Is this enough?

If I didn't change a setting then it looks to me as if they would both have the same code which can't be right?