Fixes a crash with preferences, as well as fixes a bug where a

non-existing item can be added to the list even though it exists in the
users preferences.
Moved a script function retrieval into a try/catch block.
Fixed a file list bug, needed to make a copy and clear; also if a crash
happened the list would never be cleared, and a script could get stuck on
one file. Scripts should have their own try/catch around each individual
file if they want to continue processing files without interruption.

code/src/TimerPlus.cs

@@ -26,14 +26,14 @@ namespace FileWatcher
         {
         }
 
-        public void Start()
+        public new void Start()
         {
             m_Running = true;
             m_Start = DateTime.Now;
             base.Start();
         }
 
-        public void Stop()
+        public new void Stop()
         {
             m_End = DateTime.Now;
             m_Running = false;