Very well done!
First off, the voices were near perfection. The voice actors/actresses have a lot of good talent. The kids in the costumes of other anime/game characters like Moogle and Rukiya were also pretty cute. If they made Kagome's house actually look like Kagome's house, this flash would've been absolutely perfect. The satritical "next-episode" Inuyasha humor of the post-credits is probably the best part of the entire flash! Accurately portrayed, voiced, and timed. The music themes are the same ones used over and over in the series, which adds to the overall accuracy of this movie being a near-real Inuyasha fanfic; preventing it from feeling like some cheap 3rd grade knock-off. If the creators of Inuyasha ever made a Halloween episode, I can image its inspiration coming from this movie. Very well done!