Nested Families with 'Family Type' parameter breaks constraints

[joshua.harter]

I have a window family (GM) in a door family (door) that I am attempting to constrain/lock to a reference plane that moves vertically.
This appears to be impossible.
I have a 'family type label' applied to the window family, that drives an 'integer' parameter to change the family type based on a 'length' parameter.
when I lock the window family with the type label to a reference plane driven by the length parameter, the constraint breaks - you know, that annoying message 'revit hates you... constraints not satisfied'. yeah.
So I've tried everything I can think of or have read, including to try locking a point not plane in the window family. no luck.
Why can I not constrain a family type driven object?

Does anyone have a workaround or solution to this problem?
Thanks,

[joshua.harter]

SOLVED:
I got to thinking about using the 'moves with nearby objects' check option but didn't know if that would get me consistent results. I did some searching and found a thread on another, more active revit forum to find out more about the option when I had the idea to 'indirectly constrain the window family, not to a reference plane, but to a nearby object, the door panel.

ANSWER: Instead of align lock or dim lock constrain the nested family with 'family type parameter', I grouped it with an adjacent panel. Then align locked the group to a reference plane that is driven by a length parameter.
Nested family now switches types at defined length, and stays constrained when ref plane moves.
I think its ridiculous to have to wrestle with software. revit sucks.

[marmiketin]

when inserting a family into another family you can control its bottom elevation height using the instance parameter located under properties when you select the object.

Attachment 104045