Creating a checkbox column in Objectlistview with Revit

Question

I am trying to create a list of sheets in Revit using the ObjectListView control using vb.net API. I have managed to use the column aspectgetter and aspect putter to create delegates that get the parameter values for various parameters in the sheet family, and this seems to be working correctly. Now I want to have a check box column at the front of the list to allow the user to make a selection of sheets - there does not seem to be an easy way to do this as I believe I need to tie the checkboxes to a parameter in the sheet family?

I have experimented with creating a boolean shared parameter in the sheet family and then tying the checkbox column to this using the BooleanCheckStateGetter/Putter but it doesn't seem to be working?

.BooleanCheckStateGetter = Function(ByVal rowObject)
                                           Return CType(CType(rowObject, ViewSheet).LookupParameter("checked").AsInteger, Boolean)
                                       End Function
.BooleanCheckStatePutter = Function(rowObject, newvalue)
                                           CType(rowObject, ViewSheet).LookupParameter("checked").Set(If(newvalue = True, 1, 0))
                                           Return newvalue
                                       End Function