The Maison Ikkoku movie takes place in the middle of episode 96 of the series, so you probably shouldn't watch this until you finish the entire series. Unfortunately, since it takes place in such a small time frame (after Kyoko returns Souichiro's belongings but before the wedding), there really isn't much room for character and story development.

This movie combined everything that was so great about the series into one episode. Comedy, romance, it's all in there. For ninety minutes. Maison Ikkoku is great and all, but when a single episode drags on and beats around the bush for ninety minutes, it's just a little too much Maison Ikkoku for one jellyfish. Also, most of the things that happen in this movie bear no actual relevance to the storyline and just seem to be there in order to introduce characters that were in the show/manga and take up time.

However, in the end the movie accomplishes exactly what it sets out to do: tell the people watching when Kyoko began to fall in love with Godai. It's a heartfelt five or six minutes in the end that are interrupted by the predictable: all of the tenants barging into the room in a drunken stupor. One things I really liked about this though is that it showed some of the characters for the first time after they had mysteriously disappeared from the show. Yagami and Ikuko are the two that I'm referring to. Kentaro and Kozue don't make an appearance in the movie but you probably saw them in the last episode of Maison Ikkoku.

There was another movie created at the end of Maison Ikkoku that was a summary movie. It shows many of the highlights from the series and is definitely something that you should watch if you don't have the time to see all 96 episodes of Maison Ikkoku.