Keep drilling games. -4 is too close to being perfect and you don't wanna let it sit there. Other than that, @Pacifico's advice is great and you should follow it.
Yup, do all of the games (or most of them) until you're comfortable doing them perfectly. Don't waste your great work in the other sections by settling for anything less than perfect in LG!
The best prep for RC is reading a lot of RC passages. You have more than 300 passages, already the perfect length and subject matter (not to mention level of difficulty).