Pokemon White Rom crashes at same point in game.

Hey guys,I know I'm new here but if you could help me that would be great.So I got a Pokemon White rom for my R4 SDHC card. (its this card: http://i55.tinypic.com/69o082.png only with a wi-fi logo thingy added).The rom worked fine after I installed the latest Firmware update. However, I've beaten 5 gyms and on my way to Twist Mountain.Cheren shows up and wants to battle and during the battle the game will always freeze/crash.It surprised me because I got past the battle earlier, it crashed somewhere on Twist Mountain (I forgot to save) but I didnt really think much of it. However, now when I restart it will always freeze/crash during the battle with Cheren.Anyone that has anything similiar or anyone that knows what the problem/solution is? My first thought was that the problem is the .ROM file and not my DS but I dont know for sure because I dont have any other DS-es nearby.Thanks in advance!

Bump. Still having the same problem only I'm further in the game.What I did was change roms (used same .sav file) and update from Firmware 1.34a to 1.35b. This seemed to fix it, until after the league. I started traing in the newly opened areas and after a while it started freezing again. I've noticed it seems to freeze when I'm switching pokemons or using items in battle.

i can't even get pokemon working, i could only get one file that doesn't save, i have the same r4 as new, link me to the file, and maybe i can take a look :)

This happened to me, but at Resort Desert before Team Plasma at Relic Castle. I fixed it by flying somewhere else and then returning.
But I think the problem was because I was using the Walk-Through Walls cheat. Are you by any chance using that cheat?