Error Message:

Could not complete ElumTools command:  AddCalcPointsSpaceCommand Exception:System.NullReferenceException: Object reference not set to an instance of an object.   at ElumTools.ElumToolsCommandCache._Closure$__11-0._Lambda$__0(CalcPointsDefinitionInstance d)   at System.Linq.Enumerable.WhereListIterator`1.MoveNext()   at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)   at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)   at ElumTools.BoundaryElement.get_CalcPointsDefinitions()   at ElumTools.AddEditCalcPoints.Add(UIDocument doc, IEnumerable`1 boundaries)   at ElumTools.AddCalcPointsBoundariesBaseCommand.Execute()   at ElumTools.ElumToolsCommand.ExecuteCommand(String& message, ElementSet elements)   at ElumTools.ElumToolsCommand.ExecuteInternal(String& message, ElementSet elements)   at ElumTools.ElumToolsCommand.ExecuteTransaction(ExternalCommandData commandData, String& message, ElementSet elements)   at ElumTools.ElumToolsCommand.Execute(ExternalCommandData commandData, String& message, ElementSet elements)


This is caused by WorkSharing Permissions not allowing ElumTools to edit the current view/link.

It is possible for this to work one day and then not work the next because of changes to the permission!

To Troubleshoot, set as much as possible to "Editable" in the Collaborate > WorkSets. 

Remember to check views and families as well as Linked Models.

An easy way to troubleshoot is to attempt to Re-Initialize the project. If that succeeds, then the other problems are most likely fixed as well.