I think the EndpointType.cs file has a problem with the enums. They are marked as [Flags], but there are no defined numeric values for the enums so they will get the default values of 0, 1, 2, 3. But when you select Interrupt you'll actually get a combination of Bulk and Isochronous (1 + 2). Either this enum class should not be attributed with [Flags], or the enums should have specific values (1, 2, 4, 8).