Coach Sean McVay has completely reprogrammed the Rams’ offense this season, but there’s one software bug: they haven’t been able to get their offense started at home. It’s a bit like one of those on-screen spinning wheels of frustration. Wait and wait and wait, and eventually the Rams will score at the Coliseum — perhaps a lot of points — but more than ever, it’s important for the Rams to put some points up early when they face the New Orleans Saints on Sunday. The Rams have not scored a first-quarter touchdown in four games at the Coliseum this season, and this week they face a Saints team that averages 30.2 points per game, third-best in the NFL. It’s notable that the Rams also have not allowed a first-quarter touchdown at home. They’ve allowed two field goals and have scored on two field goals and a Trumaine Johnson interception return. On the whole, that’s an acceptable trade-off, but the Saints have the best offense the Rams have seen this season, and they’ve won eight consecutive games with a balanced run-pass attack. The Rams would be wise not to fall into a significant early deficit and expect second-half magic. “We’ve got to have a better start then,” McVay said. “Anytime that you play against a great team like this, it’s about playing four quarters and we’ve got to come out from start to finish. You always talk about finishing games, but especially against a team like this, where they have no weaknesses, coming in on an eight-game win streak, we don’t have the ability to start slow in any phase of our team as a whole.