Bruce:
90 countries!
You really have been around! 
I would imagine that CR will be different than many of the countries that you have been to. Unless the list includes other Latin American countries. You may have already acquired many of the skills necessary for CR though.
In CR the MPs operate a lot like the brothels in Europe. The price is fixed and there is (usually) a number of girls to pick from. Outside of the MPs, strip clubs, etc., it is pretty much all free-lance action. The girls frequent any number of bars, etc. and make themselves available for action. I would compare hooking up with one of these girls a bit like approaching one of the window girls in Amsterdam, if you have been there before. After the initial impression, everything else is up for grabs. You need to negotiate time, services and price. The difference is that instead of ducking into her kammer you will take her to your hotel room.
You will definately be staying the right place to meet other VIPs. Try to find someone to be your wingman and listen to the advice that they give.
Forget the diccionario. They don't work well on the fly. I would recommend that you print out the Spanish lesson in the Newbies section and study it until you arrive. There are phrases in there that you won't learn in school.
Most of the girls can speak a little English. At least enough to get the deed done. If you can learn a little Spanish things will work better for you. The universal language in CR is $$$ though!
If you decide to frequent CR I would definate recommend that you invest some time in learning the language. Even a little can take you a long way.
Stay loose and have a good time!