"Warner Brothers did it on their series ALL THE TIME! Taking plots from their Western and Detective Film and adapting them without credit."
I'm reminded of the BATTLESTAR GALACTICA 2-parter (actually the 2nd story they filmed), "The Gun On Ice Planet Zero". It was a sci-fi amalgamation of several stories all at once-- "The Guns Of Navarone", "Ice Station Zero" (both Alistair Maclean), with "The Dirty Dozen". but, it also was a remake of the 2-part 1974 STAR BLAZERS sequence, "Pluto Reflex Gun". If you watch both to compare, it's very clear that the original Japanese version makes 10 TIMES more sense! (Glen Larson just didn't let that stop him.)
It made virtually zero sense in the BG version to describe the entire fleet being "herded" thru a "narrow lane"-- when they're IN SPACE!!! On SB it made far more sense, as until they were fired upon, they had NO idea there was a weapon on Pluto at all, and they were already heading there to make some repairs. The shock came when not only were they fired on from the planet's surface, but trying to get out of its range failed because the lazer beams were being bounced AROUND the planet by an entire series of orbitting satellites. One of the most incredible moments in the entire year-long storyline was when The Yamato, damaged, SANK beneath the waves of the "frozen" sea on the surface of Pluto. (Of course, it was a spaceship-- but it also had underwater submarine capabilities.)
The American version was a JOKE compared to this. It actually did work, for the most part, relying entirely on character drama. Good thing, on technical logic it failed abysmally. (It's no wonder so many compared the writing on BG to LOST IN SPACE.)