CBS didn't lose those rights.I don't know where this fable that they didn't stupidly lose control of half of their IP is coming from. It was for precisely this reason that we never saw a Sovereign class starship or any of the movie assets at all in DS9 - licensing can be a bitch.
They just let Paramount use that stuff exclusively while making the movies.
I don't know it you've noticed, but everything that was merchandised during the TOS/TNG movies also carried the CBS logo.
