When importing ESM2011's event browser views during an upgrade to ESM2012, they might not work properly after the upgrade. Certain field names were changed which were not converted.
EventsManager 2012 build 20111130
If a view had a condition in ESM2011 against the Computer field, this won't work in ESM2012 as the field is called Monitored Machine in ESM2012 and is not converted.
This issue has been fixed in SR1, therefore, it is recommended to update to SR1 and use SR1 installer kit.