Startup Error

I have tried installing the Supernatural Expansion on my 64-bit computer (I already own the orginial disc for the base game), but when I try to start playing it, I get this error message telling me there was an error during startup, and that I have to check the log for details. I have no idea what this means, so I tried using the ultimate fix I found in this forum. Of course, I only get to step 11, where I have to open the launcher, when I get the samme error-message again.

I have also tried hexorcists registry helper, and when I try to fix either the base game or supernatural (not that any of them have any of those symbols in front of them), it just tells me that the value can't be zero. Am I supposed to click the "Delete all value" here, or what? This seems a bit to permanent for me who have no clue what I'm doing to do.

Please help me!