Just a note, you said you bought a wireless antenna for use with your WAP (I assume). The range problem still stands as before, though. You now receive data from the WAP at farther ranges but your wireless devices will still have a problem sending back to it. It's the same problem that satellites run into. Your best bet it to get a wireless repeater or something and move it into a central location. I guess this all depends on the venue. I'd imagine without an antenna on anything, you could get mediocre reception on a big gym. (This was true in the PBG regional.. I tried messing around with an ad-hoc network. Worst signal strength I saw was about 25%)
Also, some notes on wireless security. The simplest way to secure your WAP would be to enable MAC filtering (so that only the computers you add to the list can connect), disable SSID broadcasting (makes it so the router doesn't say "Hey! Look at me! I'm a WAP!" and I don't believe wireless stumbler programs will find it unless they can put your card into passive mode), enable WEP (this is definitly not super-secure, it will just keep passer-by's out but will still let l33t h4x0rs in with enough patience), and the NUMBER ONE bit of advice is to CHANGE THE PASSWORD. It's SICK how many people don't do this one simple thing. Someone could login to the router with the default u/p, upload 'new' (read: corrupted or bad) firmware. Boom. WAP = dead. Also, if you really want to get secure, I'd set up a VPN with IPSEC stuff. But I don't really want to get into that.. since that's pretty much overkill for a WAP at a FIRST competition. Also, be smart. Anything you transfer over a wireless network can be found by anyone with the means to intercept. Passwords, credit card numbers, super-secret super weapons whitepapers.. all insecure on a basic wireless network.
Also, the only networks I found at PBG was an ad-hoc network and a WEP-protected from the Red barons. (Not to mention the unencrypted network named 'CVSretail' on the way
) I was surprised that Pitt didn't have a public wireless network. I had really wanted a way to send emails and such without paying $.25/min on the hotel computer thing.