RenderSettings: The Render Method Dropdown Listener calls the Y Resolution Input's moveCursorBy() Method to recalculate the aspect ratio if neccessary, resolving https://trello.com/c/unn8VGbf/

src/main/java/eu/crushedpixel/replaymod/gui/GuiRenderSettings.java

@@ -460,6 +460,8 @@ public class GuiRenderSettings extends GuiScreen {
 
             yRes.setCursorPositionEnd();
             yRes.setSelectionPos(yRes.getCursorPosition());
+
+            yRes.moveCursorBy(0); //This causes the Aspect Ratio to be recalculated based on the Y Resolution
         }
     }
 }