The following error may appear when appifying a SharePoint list if the lookup column references list with no Item content type.
"SmartObject Server Exception: Error refreshing Service Instance 'portal_denallix_com'. Service returned: 'Value cannot be null. Parameter name: k2List '."
Before You Begin
Currently lists without a content type being referenced as lookup column is not supported. Please see the following reference for supported SharePoint artifacts:
Adding OOB SharePoint "Item" content type to the list being referenced in the lookup column will allow the list to be appified successfully.