I just went to battle Anastasia today and had the same problem. I tried re-extracting the zip file with 7-zip, but it's still a no go. The error says: script 'interpreter' line 276 Runtime error occured. This has actually happened with other pokemon, like dedenne, but I could just avoid that trainer. Not this time!
Same issue here. I hope this gets resolved with the next patch. I'm losing my marbles!