As noted in the log file the web server is just ignoring the -f flag, so that is not a source of your issue.
However if you are using a URL Rewriter you may want to see if an updated version exists.
The two messages which I find interesting in your server error_log are:
Code:
[client 127.0.0.1] File does not exist: /usr/local/apache/htdocs/scrape
Use of uninitialized value $1 in concatenation (.) or string at /usr/local/cpanel/cgi-sys/fourohfour.cgi line 31.
It's pretty rare to see requests from localhost for broken files or requests to cpanel when trying to log into Zen Cart's admin interface.
What is in your error logs for Zen Cart?