And now I cannot achieve Thiro's CG because I don't see Sparky's challenge at Thiro's location. Sparky's CG is locked like this.
The scene number was set to the wrong variable. It's not related to your problem but an issue I fixed for the next upload.
Have you finished Brad's solo challenge in the Black Twin Towers of Honor?
If that is also not the problem, can you send the save file with the issue to my mail at Naughty-Netherpunch@web.de ? You can find the saves in the www/save folder. I only need one .rpgsave file with the number of the save slot in which you have the issue.