Can’t get past opening cinematic in L4D2

I’m on v.2.0.4.5 using standalone 2.4. I prefer stryders loader because it loads way faster than revcrews. However, when i try to start the game after the opening cinematic it says “no permissions to run left4dead 2”. This only happens with the stryder loader and not the rev crew which takes like 1 min to get to the main menu. How do i fix thiS?
Answer #1
Try right click the loader or whatever you use to start the game and click run as administrator