what type of file are you editing? .mdb or .accdb? If the former, it is likely that themes cannot be applied since themes were not an option back then. You would need to update to .accdb which is easy enough (File>Save and Publish) if you are not using functionality which has been discontinued.
you won't be able to use a .accdb with access 2003 or earlier. Should be able to use with Access 2007 or later providing you are not using functionality that was not available then. However since you are coming from a .mdb this will only apply to functionality you add subsequently. See this link for a history of changes between versions
The database was saved as Access 2002 - 2003 format, but I believe the current user version is 2012 possibly? I will have to check. The version I am on does not give me a (File>Save and Publish) option, See screenshot.