Debugger help: document how to allow CTRL+SHIFT+0 to work (to set bookmark-0)

help/Troubleshooting.html

@@ -68,5 +68,16 @@
 			<li>Windows 10 (1909) requires: 1181 x 818</li>
 			</ul>
 		</ul>
+		
+		Can't set bookmark 0 in the debugger / CTRL+SHIFT+0 not working:
+		<img style="FLOAT: right;" src="img/Change Key Sequence.png" alt="Configuration settings" hspace="5" vspace="5">		
+		<ul>
+		<li>From Control Panel...".</li>
+		<ul>
+			<li>Windows 7: Change keyboards or other input methods -> 'Keyboards and Languages' tab -> Change Keyboards -> 'Advanced Key Settings' -> Change Key Sequence...</li>
+			<li>Windows 10: Typing -> Advanced Keyboard Settings -> Input language hot keys -> Change Key Sequence...</li>
+		</ul>
+		<li>Finally set "Switch Keyboard Layout" to "Not Assigned".</li>
+		</ul>
 	</body>
 </html>

help/dbg-bookmarks.html

@@ -17,7 +17,7 @@
 		<ul>
 			<li>Set a bookmark at the current disassembly cursor, use Ctrl-Shift-#, ie:
 			<ul>
-				<li>NB. Ctrl-Shift-0 can't be used, as it's not recognised by Windows
+				<li>Ctrl-Shift-0 set bookmark 0 (by default Windows blocks this key sequence - see <a href="Troubleshooting.html">Troubleshooting</a> to resolve this)
 				<li>Ctrl-Shift-1 set bookmark 1
 				<li>Ctrl-Shift-2 set bookmark 2
 				<li>...