Follow Up - 500 Error - Issues with MarketPress and FrameMarket

I submitted a request for help two days ago and got some help yesterday but it didn't answer the question.

I'm installing the FrameMarket and MarketPress based on this how to from your site:

When I get to step five and I try to go to the user's Dashboard it gives me a Error. I'm not quite sure why. I can create the user account but not go to the dashboard and when I go to the users site, in this case it's missing the CSS files.

Here's what the error says:

Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Apache Server at Port 80

Here's what the server logs state: - - [27/Apr/2014:14:17:31 -0700] "POST HTTP/1.0" 500 582 "-" "WordPress/3.9;" - - [27/Apr/2014:14:21:50 -0700] "POST HTTP/1.0" 500 582 "-" "WordPress/3.9;"