Hi mordred,
I would like for you to start with submitting some files, which files they are and where they can be found you can read here: How to Properly Report Bugs!
Then, I have a potential solution for you to try!
Here: All the characters have disappeared since the update - #2 by ArieBarsky
Please try that, and reply here if you have troubles or became stuck somewhere.
I would love to hear from you again when you have completed these steps as well!
Silas