✔ Summary of Themes Addressed

PID / Loop Tuner reliability: Multiple fixes to ensure correctness and consistency.
Improved MPC feedforward behavior: Major stability and performance fix.
Plotting robustness: Auto-reset and secondary axis corrections.
UI clarity & correctness: Improved tips, dialog wording, and menu synchronization.
Data-processing reliability: DFC interactions clarified.

🧭 User Interface & Usability Fixes

SB‑589 – Clarification of S‑Key + Click Behavior

Corrected tip for invoking the floating run menu.

Updated documentation string to S‑Key + L‑Double‑Click to remove ambiguity.
Ensures consistent understanding of how STOP/RUN/FASTEST quick‑actions are accessed.

SB‑481 – Window Menu Naming Not Updating After Save As

File rename now properly updates the Windows menu entry.

A complex UI synchronization issue fixed so the renamed model now appears correctly in the Window dropdown.

📊 Plotting & Visualization

SB‑588 – Secondary Axis Not Rescaling

Resolved tic‑mark scaling inconsistency between primary and secondary axes.

Y2 axis now resizes correctly after new data is plotted.

SB‑579 – Plotter Grid Not Rescaling

Underlying Microsoft Chart behavior fixed via periodic cleanup.

Automatic grid reset introduced every 15 seconds to avoid distorted axes.

🧪 PID Tuning, Loop Tuner & Transfer Functions

SB‑587 – Manual PID Gains Not Propagating to Outputs

Clarified intended behavior and updated dialog wording.

Manual entries are for comparison only; not persisted or used for output connectors.
Dialogs now clearly state this to users.

SB‑586 – PID Tuner “Use Manually Entered Values” Not Sticking

Checkbox and values now persist correctly, matching behavior of transfer-function blocks.

SB‑585 – Parameter Table Not Updating When Process Type Changes

Loop Tuner now refreshes model-parameter table immediately after changing the process type and pressing Update.

SB‑584 – Value Get Block Fetches Wrong PID Values

Behavior confirmed as expected: unconnected outlets skip calculations.
No change implemented; recommendation is to avoid fetching from unconnected connectors.

SB‑582 – Loop Tuner Keeps Bad Models When Simulation Stops

Loop Tuner now restores the last known good model at EndCalculate().
Protects users against transient or unstable states being saved.

SB‑564 – PID Tuning Incorrect for Negative-Gain Models

Bug fixed; negative‑gain transfer functions now yield correct PID tuning.

SB‑530 – Missing PID Tuning for 2nd Order & Integrator Blocks

New PID strategies added and second‑order system identification improved.

🤖 Model Predictive Control (MPC)

SB‑554 – MPC Feedforward Producing Poor Performance

Feedforward algorithm for MPC improved substantially.
Previously known issue with optimizer interactions now resolved.

📈 Data/DFC Tools

SB‑544 – DFC Relationship Tab Fails With Latest User Dataset

Issue resolved through user‑side workaround, no code change.
Problem likely linked to string-containing columns or cleaned time indices.

📁 Other Issues

SB‑588 / SB‑579 – Duplicate Tracking

Secondary axis scaling bug (SB‑588) linked and resolved via base fix in SB‑579.

Release version 2026.2.12.x