Unfortunately, it's impossible to provide support for this add-on since the website of the official developer doesn't exist. I have tried accessing all websites that are related to this add-on, but none can provide troubleshooting options. There could be 2 causes for your errors:
- The add-on is not fully compatible with the version of FSX installed on your computer.
- The add-on is bugged and contains errors that can be fixed with an update, but that's not possible without the official website.