Max: I do not leak, you leak.
Max: I told you, I blew a fuse when I totaled that electrical tower. I was checking out some daisies.
David: You crashed while looking at flowers?!
Max: See you later, Navigator.
Carolyn McAdams: You know, you're cute. Did a girl ever tell you that before?
David Freeman: Nobody but my mom, but I don't think she counts.





Answer: Carolyn wouldn't have wanted David anywhere near the UFO as it could've been dangerous, so it's safe to assume that "Max" programmed the R.A.L.F robot. Although Carolyn didn't have anything to do with with David's escape, it wouldn't have escaped unnoticed that the R.A.L.F robot was in the hanger where the UFO was. Given that she's always the one with the R.A.L.F. robot, it's safe to assume she was acting worried that she'd be blamed rather than acting "shifty"