diff --git a/tools/osx/INSTALL.readme.rtf b/tools/osx/INSTALL.readme.rtf
index dea38c37f..bffc9bae5 100644
--- a/tools/osx/INSTALL.readme.rtf
+++ b/tools/osx/INSTALL.readme.rtf
@@ -1,7 +1,11 @@
 To install the RawTherapee application:
 
 1. Open the RawTherapee .dmg Disk Image included alongside this document.
-2. Drag the RawTherapee icon onto the /Applications folder icon
+2. Drag the RawTherapee icon onto /Applications.
+3. If RawTherapee.app exists, click Replace in the dialog.
+4. Do not move or rename RawTherapee.app
+
+Note: For security reasons, RawTherapee MUST be installed in /Applications. RawTherapee will refuse to start if installed elsewhere.
 
 To run the RawTherapee application:
 
diff --git a/tools/osx/rtdmg-bkgd.png b/tools/osx/rtdmg-bkgd.png
index a8be0cec6..23d434290 100644
Binary files a/tools/osx/rtdmg-bkgd.png and b/tools/osx/rtdmg-bkgd.png differ