You said you are changing an existing parameter to be a shared parameter by doing:
>* Type properties > select parameter 'doorsize' > modify > change to shared parameter >
That means that you are loosing the 'doorsize' parameter; you are not actually changing it. The error might be due to this missing parameter, which was probably required for Revit to make the door.
If you need a new shared parameter, you had better use the Add button, instead of Modify.
Alfredo Medina
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Alfredo Medina _________________________________________________________________ ______
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