Don't know what you mean about creating a new page.
I meant the link "Adding a new museum" from the home page (http://www.the-athenaeum.org/sources/update.php?a=a1).
I think this bug occurs because you entered the name of the museum in the field "Name in English" and left blank the "Primary name (required)" field. The "Name in English" field is only for the translation of non-English speaking museums. Maybe Chris should write it this way in the form. I agree that it's misleading.
In addition, you no longer have to add the location of the museum after an hyphen ( '- Norwich' in this case) as it is now automatically displayed in the dropdown menus and the museum list.