I don't think there's any right way to adapt a visual novel. It's a medium often overlooked by the western anime watching community, but the influences of those early gal games are strong across many genres of anime. Many of the character archetypes we find so common today can trace their origins back to visual novel tropes. The problem when adapting these things, and trying to do it faithfully, is the choose your own adventure nature of vn storytelling. How can you faithfully adapt every route, every choice? You can't, without making some fans angry. Best you can do is adapt the common route, throwin a few episodes with hints of some of the other girls' routes and adapt the good or true ending with the main heroine. Then make side content like this.

I guess I should say that I never played any of the original visual novels. My knowledge of Little Busters is solely based in the anime adaptations supplemented by cursory wiki reading to fill in the gaps. Frankly visual novels are a huge time sink and I've got enough in my plan to watch to merit not wanting to spend more time on extra homework. My assumption is that this movie exists in a sort of alternate route from the main story, where Kud is the main heroine that Riki focuses on. That's just the best I can come up with from conjecture.

I really liked Little Busters, and certainly this story won't make much sense if you aren't familiar with that story. This is like a fun little side adventure in that world they created together. It ends on a more poignant note with Kud being the girl to pull through. It actually isn't clear what the fate of the rest of them is in this version. I don't remember them saying anything about it anyway.

So if you were a huge Kud fan and wanted Riki to choose her as his best girl here's the story for you. If you prefer the more generic ending you can just think of this as non-canon, or make up whatever ending you want, really. Like I said at the outset, there's no right way to adapt a visual novel. If you're a purest you can just dump the 80+ hours into playing the original game. Have fun with that.

8/10