diff --git a/demos/99-bt.c b/demos/99-bt.c
index 186e3ad..2cb01cb 100644
--- a/demos/99-bt.c
+++ b/demos/99-bt.c
@@ -81,7 +81,7 @@ void draw_scene() {
 
         for( int y = oz; y < (oz+dd); ++y )
             for( int x = ox; x < (ox+ww); ++x )
-                chunk[ (x + W/2) + (y + Z/2) * W ] |= 1;
+                chunk[ (x + W/2) + min(y + Z/2, Z-1) * W ] |= 1;
     }
 
     ddraw_color(BLUE);
@@ -260,4 +260,4 @@ void move_players() {
         ui_label2("Robot", ICON_MD_GAMEPAD " I,J,K,L keys");
         ui_panel_end();
     }
-}
+}
\ No newline at end of file
diff --git a/tools/cook.ini b/tools/cook.ini
index 660afab..97a8e88 100644
--- a/tools/cook.ini
+++ b/tools/cook.ini
@@ -1,4 +1,4 @@
-; this is where you specify and configure the V4K pipeline.
+; this is where you specify and configure the FWK pipeline.
 ; tweak the pipeline and add new importers just by editing this file.
 ; there is no flow control in this script file: lines are parsed and evaluated, from top to bottom.