In Max 5 (which I’m still using for production), I can create an abstraction that contains the object
[adc~ #1 #2]

thereby creating an adc~ with two ports which can be wired up as usual to other objects. When I instantiate the patcher, I would pass in the port numbers as arguments, e.g.
[ChannelStrip 5 6]

This works perfectly fine in Max 5.

In Max 6.0.1 however, after creating [adc~ #1 #2], only one output port appears and so it is not possible to wire it up to other objects.

Unless I’m missing something (always possible) this is quite nasty.