Thank you for your post!
1. If the screen freezes when you submit, give it a few minutes before you log out and back in. If you do not see 'Start Assessment' or 'Resume Assessment', you can safely assume that it submitted correctly.
2. Due to the anonymous nature of LPI, it is not possible to verify if a particular observer has definitively responded. You can see who has started the assessment by looking at the manage observers page within the LPI admin account. If there's an 'Edit' link in the language column, then the observer has not started the assessment. If there is no 'Edit' link, and it simply says the language (ie. 'English'), then they have either started or completed the assessment.
3. You can contact LPI support by calling 877-591-7762. LPI sales can be reached at 866-888-5159.
4. Verify the leader registered with the same email address that the assessment was assigned to. If they did not, the leader willl need to add the assigned assessment email address as an alias to their Account Info page. If any leaders or observers are missing their assessments, please feel free to direct them to technical support.
I hope this helps answer your questions. Please let me know if there's anything else I can assist you with. Have a nice afternoon!