Changed model and script to allow plotting the port variables.
Reverted commit that exposes staA instead of sta_a
Reformulated model to avoid an event iteration.
Reformulated computation of states at port to avoid an event.

This is correct because the variables can only be used for reporting,
because they are conditionally enabled.
Reverted model to use MSL functions as the bug is fixed in MSL 3.2.1
New reference results due to change in event handling.