Thanks, Norbert.
Tech Support has acknowledged the issue, while not yet calling it a "bug".
To me, it seems like a bug, in that when the App Builder converts "L.lvlib:X.ctl" to "L.lvlibp:X.ctl", it should also convert "Queue of L.lvlib:X.ctl" to "Queue of L.lvlibp:X.ctl".
Workarounds include:
1... Living with it as it is. That means you cannot CREATE CONSTANT from the queue inputs, you have to open it from the PPL directly.
2... Putting the TYPEDEF into one PPL, and the queue-creation code in another. That means the queue is guaranteed to be of type "Queue of L.lvlibp:X.ctl".
3... Haven't tried this, but building the PPL with DISCONNECT FROM TYPEDEFS might work, as all the controls get reduced to plain controls, by that.
So, there's nothing left to do here.
Thanks, all.
Steve Bird
Culverson Software - Elegant software that is a pleasure to use.
Culverson.com
Blog for (mostly LabVIEW) programmers: Tips And Tricks