Are you trying to add IVIM ESX Server resource as Custom Object resource to Summary view?
If yes, then this is not supported in the current version.
To fix things, you will need to go to Admin, Customize View and remove the failing resource from the view.
Martin - yes, we were trying to use the VM CPU Consumption, which is an ESX resource. Thanks for the fix!
You stated it is not supported in this version - did you mean the beta build or the final release version? If the answer is the final release version, then I'd suggest the resources be filtered to show only the allowed resource types that are supported.
In final release there will be support for virtualization resources implemented but it might be not all of them will make it. You are right that resources that are not supported cannot be part of selection list, that's a bug and we are working on a fix.
Thanks for your feedback,