Can you check which is the object from the error "Object doesn't support this property or method".
Telerik.Sitefinity.WorkflowActivities.dll is no more used and it is not distributed. Its data was merged to Telerik.Sitefinity.dll in one of the previous releases.
Telerik.OpenAccess.MySql.Data - it is also not required, you can remove the reference.
Telerik.OpenAccess.40.Extensions.dll - you should be able to reference this dll from Sitefinity 4.1 bin folder.
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