diff --git a/src/TeamsISO.App/MainWindow.xaml b/src/TeamsISO.App/MainWindow.xaml
index 2322d4a..cb2eb2b 100644
--- a/src/TeamsISO.App/MainWindow.xaml
+++ b/src/TeamsISO.App/MainWindow.xaml
@@ -410,23 +410,36 @@
             <!--
                 Participants table — v2 "Studio Terminal" layout.
 
-                Five columns:
+                Seven columns (left → right):
                   1. State LED        24px  — 8×8 hard-edged square. Filled cyan
                                               when LIVE; filled coral on ERROR;
                                               filled amber on NO SIGNAL / STARTING;
                                               hollow neutral when OFF.
-                  2. Name + caption   *     — DisplayName (Inter 13/Medium) plus
+                  2. Preview thumb   106px  — 96×54 (16:9) WriteableBitmap fed
+                                              from the engine's most recent
+                                              ProcessedFrame at the 1Hz stats
+                                              tick. Em-dash placeholder when
+                                              no pipeline is running.
+                  3. Name + caption    *    — DisplayName (Inter 13/Medium) plus
                                               source machine + state label below
                                               in JetBrains Mono 11/Tertiary.
-                  3. Audio meter      110px — five vertical hard-edged bars,
+                  4. Audio meter     110px  — five vertical hard-edged bars,
                                               each lit when DisplayedAudioLevel
                                               crosses its threshold (0.2, 0.4,
-                                              0.6, 0.8, 1.0). No averaging.
-                  4. Output name      150px — JetBrains Mono 12 — the NDI source
+                                              0.6, 0.8, 0.95). No averaging.
+                  5. Output name     150px  — JetBrains Mono 12 — the NDI source
                                               name TeamsISO broadcasts as.
-                  5. ISO toggle pill  110px — LIVE = cyan-muted fill with cyan
-                                              text; OFF = hollow neutral; ERROR
-                                              gets the existing trigger swap.
+                  6. CFG (gear)       56px  — U+2699 glyph button; opens the
+                                              per-participant override editor
+                                              (framerate / res / aspect / audio).
+                  7. ISO toggle      124px  — rounded-rect Radius.M button. LIVE
+                                              = cyan-muted fill with cyan text;
+                                              OFF = hollow neutral; ERROR gets
+                                              the existing trigger swap. Width
+                                              124 chosen so 'Enable' and
+                                              '● LIVE' don't clip at the right
+                                              edge after the corner-radius
+                                              change in 25229bd.
 
                 Row height 52 (down from 56). Active speaker = full-row
                 bg.active-speaker tint set by the global DataGridRow style
@@ -641,11 +654,11 @@
                             </DataGridTemplateColumn.CellTemplate>
                         </DataGridTemplateColumn>
 
-                        <!-- Col 5 — ISO toggle. LIVE = cyan-muted fill + cyan border + cyan text.
+                        <!-- Col 7 — ISO toggle. LIVE = cyan-muted fill + cyan border + cyan text.
                              OFF = hollow neutral. Error states use the existing IsoToggle style.
                              Width 124 (was 110) so the "Enable" / "● LIVE" content has breathing
                              room inside the rounded-rect — 110 was clipping the label at the
-                             right edge once the IsoToggle stopped being a full pill. -->
+                             right edge once the IsoToggle stopped being a full pill (25229bd). -->
                         <DataGridTemplateColumn Header="ISO" Width="124">
                             <DataGridTemplateColumn.CellTemplate>
                                 <DataTemplate>