The scanner will do exactly what the regex in your configuration tells it to do. How to specify and order the regex so it works the way you want it to depends on the structure of your filing system and naming convention. At a glance, I'd say (?i)^.*\\(?P<title>.*)\\.{0,2}\..{3,4} looks like one that does what you describe. If this is so, it's because no matches are found with previous expressions, and this one matches because of the 0 to 2 "." in the filename. As a result, the title is determined to be "Spillefilm.dummy" and the title in the filename is ignored.
You'll have to consider the impact on your other file pathnames, but something like (?i)^.*\\[Spillefilm.dummy]\\(?P<title>)\..{3,4} (if encountered before any other expression that produces a match) would take care of this particular situation.