Very cool. We have 2 subs in common (/r/crossfit & /r/actuallesbians) and I'm 5'4" so I know the short chick CrossFit struggles. I'm CF-L1 certified, so if you have any questions on scaling you can hit me up. You were specifically asking about starting CrossFit at your ability and at 210..and I totally recommend it, but you should ease in. I would take it easy on things like box jumps and Olympic lifts when you're starting. Does your gym have an "on-ramp" type of course? Most legit CrossFit gyms these days will have a private-ish starter, on-ramp, course to teach all the movements and to ease you into the intensity, etc. I'll be a bit concerned if they don't. Most boxes have figured out that it's a better/safer experience for newbies to come in through a private/small group introductory type system. Does yours?
Literally every single movement has some type of scaling and you'll want to scale intelligently when you're starting. I believe that intensity is trained, just like everything, over time. In the beginning you just want to pick the right movements and time domains to challenge the body but not shock the ligaments, tendons, connective tissues, etc.
Also, I wouldn't worry much about the 1500-1700 cals when you're just starting; I would prioritize protein in general (to build muscle and to repair ligaments/tendons/etc) and I would make sure to fuel pre-WoD. Like seriously, an apple and half a protein shake go a long way before a workout. Don't go in starving, you need your wits about you to make good choices and to keep the movements at a high quality. Live to fight a "give it everything I've got and be left in a puddle on the floor" another day.
If you can check the WoDs ahead of time and think out your scale/progression that would be ideal. Sometimes you can see other average times and you can get a feel for, "oh, this is supposed to be short and fast" or "longer and keep moving". Ideally good coaches can help you with this beforehand; go early. But, don't forget that you have to own your own training and don't be pressured into doing anything that isn't smart for you.
I also have to say, that, honestly, I was a little nervous heading into CrossFit and being gay because I've been through some bullshit (I'm 42 and from the South), so the level of acceptance at my box (and at many others) has TOTALLY blown my mind. They're like family. The acceptance is amazing; everyone just wants everyone to be healthy and to work hard to be able to enjoy life. They really are the best people! So, good luck and have fun.