diff --git a/Sources/VLSheetView.mm b/Sources/VLSheetView.mm
index 52ca927..1156735 100644
--- a/Sources/VLSheetView.mm
+++ b/Sources/VLSheetView.mm
@@ -628,7 +628,7 @@ const char * sBreak[3] = {"", "\xE2\xA4\xBE", "\xE2\x8E\x98"};
 		// on top.
 		//
 		if (fSelEnd != kNoMeasure && fSelStart <= fSelEnd 
-			&& fLayout->FirstMeasure(system+1) > fSelStart-(fSelStart==fSelEnd) 
+			&& fLayout->FirstMeasure(system+1)+(fSelStart==fSelEnd) > fSelStart 
 			&& fLayout->FirstMeasure(system) < fSelEnd+(fSelStart==fSelEnd)
 		)
 			[self highlightSelectionForSystem:system];
diff --git a/Sources/VLSheetViewSelection.mm b/Sources/VLSheetViewSelection.mm
index 1372d2d..3b50fd2 100644
--- a/Sources/VLSheetViewSelection.mm
+++ b/Sources/VLSheetViewSelection.mm
@@ -41,7 +41,9 @@
 {
     fView   = view;
     fAnchor = anchor;
-    [fView selectMeasure:fAnchor to:fAnchor];
+    dispatch_async(dispatch_get_main_queue(), ^{
+        [fView selectMeasure:fAnchor to:fAnchor];
+    });
     
     return self;
 }