The messages.properties file does not contain some of the message keys that are in the other message files.
Messages that use line-continuation should contain a space before the \ operator.
Several words inside the message files seem to be joined up, looks like a result of the second issue.
The following messages seem to be "LEGO", this could be solved by combining messages or adding parameter support: LoggedInAs_t, MatchesFor_t. ThisIsEuropeana_t, APlaceToShareIdeas_t, UsernameInUse_t, AnEmailHasBeenSentTo_t.
Language and country names could use the CLDR or built-in Java functions where possible to avoid the duplication of effort in translating this.
