L4D2 - 2v2 - Another 2v2, cuz my 4v4 is taking too long

what the title says...and I need to figure out how to get the vegas pro preview window to play without lag...can't really tell sometimes how my clips will turn out :( http://www.mediafire.com/?2gal7wqvsry61pg - for the HUD "Copyright Disclaimer Under Section 107 of the Copyright Act 1976, allowance is made for "fair use" for purposes such as criticism, comment, news reporting, teaching, scholarship, and research. Fair use is a use permitted by copyright statute that might otherwise be infringing. Non-profit, educational or personal use tips the balance in favor of fair use."