Other than just keeping at it, Meg, I'd also recommend trying to really focus on hitting the first few weeks of a new release. Part of the challenge in getting the moves right is also knowing what's coming next. If you're never sure of the music and the next steps, you're trying to both work on your current move and listen for the next.
When they're in a 4 week launch of a new release, things are steady on the sequence front, so it makes it easier to learn the actual steps. After getting one release down, it becomes a lot easier to keep up (or so I found :))
Good luck!