yeah, you can diy they say in about 1-2 hours and there is a video to buy for $40 that explains it and i believe its on sale at half off which is pretty cheap considering the dealer will charge a fortune to fix the problem! the website is www.bmwtwistedseatrepair.com
good luck! i currently have the same problem but will wait til spring to fix it! he has a free video on his website explaining the procedure and stuff!