I created a temp folder, but for the script to write to it successfully from the cgi folder "Other" seemed to need Write & Execute privilages.

Without any additional information, I'm guessing it's because the directory's user and group ownership were set to something other than what the CGI script was running as. When a web server executes one of your CGI scripts, it runs as the same user as the web server process, unless the web server explicitly changes it. Even if the web server does so, your directory probably does not have the correct user/group ownership.

One solution is to look at the user/group ownership on the file created by your CGI script. This will tell you what user/group the CGI process is running as. Use the same value on your temp directory, then you should be able to set that directory's permissions to "rwx------".