Possible bug: Graph not showing input movement in DR/Expo page in some cases

DS24 FW4.28

Recently I wanted to create dual rates on nosewheel steering, and in addition to that, I wanted to stop the nosewheel steering if I have gear retracted up.

My programming is as such:
A) create "nosewheel" function and leave as blank for "source" on function assignment menu.
create free mix: Master "Rudder", Slave "Nosewheel", throw "100%", switch "SG". Effective if SG is ticked. else no mix. SG is the retract switch.
C) On additional section, tick "slave dual-rate" to enable. This allows the slave to have its own dual-rate separate from master.
D) "Rudder" does not have dual rates configured.
E) create "Global" "nosewheel" dual rate with switch "SC" to restrict nosewheel to "50%" throw if active, else 100%.

What I discovered is that after this is configured, the graph beside the dual-rate configuration will no longer move according to rudder inputs. SG is not active, so rudder input is 100% mixed to nosewheel.
However, the receiver output reflects the true dual-rate effective of rudder inputs for the nosewheel. This is also verified physically with the servo moving.
Yet on the graph, the input is dead centre stick only. This is true, regardless of SC switch position.

Hence I suspect this is a bug, although minor as the actual output to servo still works. Except that the graph is no longer reflecting the output it should be (what is shown in the receiver/servo output menu).

Jeremy