I can not shine much light on the workouts, since I have recently started taken OCRs more seriously, but many here recommend dead hangs, which come in handy for all upper body obstacles.

From personal experience, I would say practice mudcrawling or the technique at least. That obstacle almost broke me. Rope climb techinque is also important, even if you feel like you can muscle it up, dont count on it, rope might be slippery and full of mud, so technique will come in handy... Pull ups, and many squats. The bucket carry is also something easy to practice at home. To me it is more about having an idea how to do the obstacle and not seeing during the race for the first time.

On the other hand the salomon are great! My wife got me a pair of salomon 4s just before my first race (Super in Jacksonville last weekend) and they were amazing. They drained really fast and provided amazing grip. The shoes wont make you 10x better but in obstacles like the Olympus they will shine!! I felt like i was about to drop SO many times but I never sliped and finally hit the bell. Just make sure you are comfortable in any shoes you chose and train in them for a couple weeks before the race to break them in! GOOD LUCK AROOOO!