No, currently the way the script is written, its quite difficult to filter it by a particular vCenter folder. The script currently goes through all ESX(i) host in your environment and then from there it traverses through the VMs in each host to pull out the relavent information. It's not impossible but it does require quite a bit of code change to support this.
If you're lookign for an example of how to list VMs by a particular VM folder, there is a script in the repo called "listVMByFolder.pl" which can give you a starting point.
Thanks for the info, I'll take a shot at modifying the script...if I can make it work I'll post it.