Ok, it worked.
Turns out it's just me who don't know how to properly 'install' the patch. I can finally get to the final boss.
And thanks for your support.
I think I'll replay to found out what I've missed.
Thanks again! ^^
So, I've tried re-downloading the game and the patch, and the same message still comes out. I also checked the Audio file and didn't find the BGM said in the error message.
I think this have to do with the absence of said BGM.
Could you add the missing audio?
Also, the option to give Rock covering fire still available after the fight.