I've never used the module, so I can't speak to the specific things you're requesting.

But I can speak to an assumption you're making that's incorrect. You didn't share with us the actual error message from which you made your assumptions. But if you're seeing mention of "TABLE_PROTX_FORM" then I'm certain that the actual error is that your PHP files no longer contain a define() statement to declare the definition of the constant named "TABLE_PROTX_FORM".
Much older addons would have probably directly edited the /includes/database_tables.php file to add their table names to it. Better-written addons would have added their own additional file into the /includes/extra_configures/ folder (and also same in admin side) instead. That may help you find what you skipped over when you were comparing files as part of your upgrade preparations.