Update README.rtfd for macOS 10.15 "Catalina".

Building/MacOS/README.rtfd/TXT.rtf

@@ -50,7 +50,13 @@ Hold down the "control" key on your keyboard and click on the new OSCAR icon in
 }¬}\cf2 \uc0\u8232 \
 \ls2\ilvl1\cb3 \kerning1\expnd0\expndtw0 {\listtext	B.	}\expnd0\expndtw0\kerning0
 A window will appear advising you that "OSCAR is from an unidentified developer" and asking if you want to run it. Click "Open" to grant it permission: \uc0\u8232 \cf5 \cb1 {{\NeXTGraphic Oscar-mac-7-open-confirm-with-cursor.jpg \width10640 \height6220 \noorient
-}¬}\cf2 \uc0\u8232 \u8232 \cb3 You will only need to do this the first time you run OSCAR after installing any new version.\cb1 \
+}¬}\cf2 \uc0\u8232 \u8232 \cb3 On macOS Catalina, you may first get a window without an "Open" button, so you may need to attempt this twice. You will only need to do this the first time you run OSCAR after installing any new version.\uc0\u8232 \
+\pard\tx220\tx720\tx1440\pardeftab720\li720\fi-720\partightenfactor0
+\ls2\ilvl0\cf2 \cb1 \kerning1\expnd0\expndtw0 {\listtext	3.	}
+\b \cb3 \expnd0\expndtw0\kerning0
+On macOS Catalina
+\b0 , the first time you import CPAP data from an SD card you will see the following prompt:\uc0\u8232 \cf4 \cb1 {{\NeXTGraphic Oscar-mac-7b-catalina-permissions.jpg \width10640 \height5360 \noorient
+}¬}\uc0\u8232 \cf2 \cb3 Click "OK" to grant OSCAR permission to read your SD cards.\cb1 \
 \pard\pardeftab720\partightenfactor0
 
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@@ -59,11 +65,33 @@ Troubleshooting\
 \cf0 \cb1 \
 \pard\tx220\tx720\pardeftab720\li720\fi-720\partightenfactor0
 \ls3\ilvl0
-\b0\fs28 \cf2 \cb3 \kerning1\expnd0\expndtw0 {\listtext	\'95	}\expnd0\expndtw0\kerning0
+\b0\fs28 \cf2 \cb3 \kerning1\expnd0\expndtw0 {\listtext	\'95	}
-Help, I'm getting the following error! \uc0\u8232 \cf5 \cb1 {{\NeXTGraphic Oscar-mac-8-open-error.jpg \width10640 \height6220 \noorient
+\b \expnd0\expndtw0\kerning0
-}¬}\cf2 \uc0\u8232 \u8232 \cf6 \cb3 This can happen after installing a new version of OSCAR. Open the Applications folder as shown in step 1 above and then see step 2 above to grant OSCAR permission to run.\
+Help, I'm getting the following error! 
-\pard\tx720\pardeftab720\partightenfactor0
+\b0 \uc0\u8232 \cf5 \cb1 {{\NeXTGraphic Oscar-mac-8-open-error.jpg \width10640 \height6220 \noorient
-\cf2 \
+}¬}\cf2 \uc0\u8232 \u8232 \cf6 \cb3 This can happen after installing a new version of OSCAR. Open the Applications folder as shown in step 1 above and then see step 2 above to grant OSCAR permission to run.\uc0\u8232 \
-\
+\ls3\ilvl0\cf2 \kerning1\expnd0\expndtw0 {\listtext	\'95	}
+\b \expnd0\expndtw0\kerning0
+Help, I'm running macOS Catalina and I'm getting the following warning about malware when I try to open OSCAR! 
+\b0 \cf4 \cb1 {{\NeXTGraphic Oscar-mac-9-catalina-open-1.jpg \width10640 \height6180 \noorient
+}¬}\cf2 \uc0\u8232 \u8232 \cb3 This is simply an extra step in Catalina. Click "Cancel" and then try step 2 again to grant OSCAR permission to run.\uc0\u8232 \cb1 \
+\ls3\ilvl0\cb3 \kerning1\expnd0\expndtw0 {\listtext	\'95	}
+\b \expnd0\expndtw0\kerning0
+Help, I'm running macOS Catalina and OSCAR won't import anything from my SD card!
+\b0 \cb1 \uc0\u8232 \u8232 \cb3 You may have accidentally clicked "Don't Allow" at the prompt shown in step 3 above. To fix this, open 
+\b System Preferences
+\b0 , select 
+\b Security & Privacy
+\b0 , and select the 
+\b Privacy
+\b0  tab. Scroll down and select 
+\b Files & Folders
+\b0  from the list on the left and then check the 
+\b Removable Volumes
+\b0  box under OSCAR as shown: \cf4 \cb1 {{\NeXTGraphic Oscar-mac-10-catalina-fix-permissions.jpg \width15600 \height13700 \noorient
+}¬}\cf2 \uc0\u8232 \u8232 \cb3 You may first need to click on the lock in the bottom-left corner and enter your password in order to make this change.\uc0\u8232 \
+\ls3\ilvl0\kerning1\expnd0\expndtw0 {\listtext	\'95	}
+\b I still have questions!
+\b0 \uc0\u8232 \u8232 \expnd0\expndtw0\kerning0
 The most up-to-date version of these instructions can be found at {\field{\*\fldinst{HYPERLINK "http://www.apneaboard.com/wiki/index.php/OSCAR_Installation:_Apple_Mac"}}{\fldrslt http://www.apneaboard.com/wiki/index.php/OSCAR_Installation:_Apple_Mac}}.\
 }