Fix build for latest VS2019

src/openrct2-ui/scripting/CustomWindow.cpp

@@ -1205,7 +1205,7 @@ namespace OpenRCT2::Ui::Windows
                 {
                     if (customWidgetInfo->Name == name)
                     {
-                        return i;
+                        return static_cast<rct_widgetindex>(i);
                     }
                 }
             }

src/openrct2-win/openrct2-win.cpp

@@ -18,6 +18,7 @@
 
 // Then the rest
 #include <algorithm>
+#include <iterator>
 #include <openrct2-ui/Ui.h>
 #include <openrct2/core/String.hpp>
 #include <stdio.h>