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'''Custom code compilation errorsin UBIK 5.1: Implicitly abstract classes'''
Custom code assembly improvements for UBIK 5.1 have led to the effect that obsolete "legacy" MetaClasses originating from pre-version-4 databases get in the way of building the customizing and must be either deleted or marked as abstract (setting the ClassType property to 50).
Any valid custom classes that use abstract custom code must also be marked as such via their ClassType.