The logs on the hosting machine indicate a validation error in the model.
Please make sure you validate and run the application in the studio, just before hosting.
Also, please make sure you're using the latest stable version (184.108.40.206).
If you've passed the above checklist, and even if no changes need to be made, I suggest you try hosting again.
If all else fails, you're welcome to send us the project so that we may perform additional checks.
For best results, use the Firefox browser..