Using Control Panel Java
The Java runtime language includes a Control Panel Item to customise its use in Web Pages.
C:\\Program Files (x86)\\Java\\........\\bin\\javacpl.exe
Update Advanced Security Settings
Opera and Chrome may require other changes. FireFox does not seem to support Java Applets.
Using Control Panel Java
Add Site Level Medium Java Security.
Select "Edit Site List..." add http://www.montegodata.co.uk Ignore the warning notifications.