Crashed Step 2...What are my chances?

Most applicants don’t have step 2 available for programs when they start offering interview invites so I would imagine step 2 does not play a big roll in the interview invite algorithm. You have good step 1 scores and that alone should get you past the screening process and get some interview invites granted you have good LORs, grades, etc. Step 2 scores only came up briefly during my interviews. Since it was not on file they asked if I took it yet and what I got…end of discussion (I scored 5 pts higher on step 2). From my experience people do score +/- 10 points from their step 1, so your score might raise some discussion. If there were any extenuating circumstances on the day you took step 2 I would be prepared to explain it (computer shutdown, you ate some bad sushi the night before, etc). Also fact that you are taking a year off to do research should reinforce your application and mitigate any doubts they have about your step 2 score. Just focus on your research and don’t worry about your step 2 score. It is probably the least important part of your application. And as usual apply broadly, its always easier to turn down interview invites then reapply.

The Step 2 mean this year is 238 and the std deviation is 19, so you did a little worse than a deviation below the mean, about 12th percentile among all test takers. That's not good at all. What happened? Did you not study for this exam at all?

There's not much you can do now other than kick butt on your research and publish like a machine.

No sense worrying about it as its done and you cant change it. Right now you need to focus on research and look for anyone that needs your specific research skills to find opportunities to collaborate on additional research. As said above be a machine. Also make sure you are networking with faculty and residents. Start thinking about where you want to do your aways and gather info now so you can apply early and make smart choices about where/when to do them. You have a great Step 1, your going to hopefully have a killer research portfolio, as long as you get everything else together strong clerkship evals/ strong letters/ strong aways/ etc. you are going to match don't even worry about your Step 2.