For the most part, the front of the movie version is the same the front of the TV version when it comes to Bright and Mirai, but when Bright is supposed to fall ill, he doesn't. That leaves a giant void in their relationship and cuts out some of Mirai's characterization. If you haven't seen the TV version, you will be very surpised how upset Bright becomes when he finds out about Cameron. When they cut out the "ill" part, they also cut out a major part that showed that they were becoming more than friends.
When White Base arrives in Side Six, the scene in which Cameron tells Mirai that he loves her is cut out and replaced with a scene in which Mirai tells Bright that she doesn't want to marry Cameron. Although I think the former scene was important and shouldn't have been cut, the newer scene also shows how much Bright truly cares for Mirai. It starts off with Mirai handing Bright a shirt of his that she personally mended because she thought "that the orderly wouldn't do a good job". She goes on to tell him that Cameron "is so wrong". Bright expresses her concern for her, but also adds that maybe she should at least stay in contact with Cameron. He then says, "I try to live my life as cleverly as others do, but sometimes I can be so clumsy" As he leaves, Mirai mutters under her breath "Yes, you are", showing that she is beginning to understand how much Bright does love her.
A lot of the Mirai-Bright-Cameron/Sleggar love "triangle" has been reanimated, but other than the new scene, it pretty much remained the same. However, after the death of Sleggar, Bright only asks Mirai once if she is okay, and then the subject is dropped. There was much other stuff going on at the end of the third part of the movie series there was no extra time to add more to the Bright and Mirai story. We're left to assume that they get together.