Those ( ) are called Courtesy Accidentals, and are implemented differently in different notation software. While I think the theory definition as given by Noel is clear enough, you don't often have a choice in how it's implemented.
VideoTrack and I found one case in BIAB where BIAB did NOT use a courtesy accidental and we thought they should have: an accidental early in a measure in the bass clef of a grand staff carried over into the treble clef later in the bar. Confused both of us at first, especially me since I don't play piano.
I do not think there is a checkbox in BIAB to
allow or suppress courtesy accidentals, I suggest you make a post in the Wishlist Forum.
Me? I usually like them, even in the example above. I can't tell you the amount of penciling I have made into show books to remind myself in case attention wanders in the slightest. The most important is the first note of an entrance, if there is any possible question whether there is an accidental applying, I write it in and erase it when the show is over. Don't want to come roaring in with a trumpet on the wrong pitch. Other trumpet players do the same thing, based on the erasure marks when I get the book!
You write in C? Are you one of them 'jazzers'?
We do often write in C now and let the modulations go where they will, without many key signatures.
Upon further research, I found something interesting in the Help. Look up Help, Index, Accidentals. Read about Intelligent Accidentals and the setting in the Notation Options Window. I could not solve your problem, though.