To transfer files off an NTFS formatted USB HDD, here are the steps:
Connect your USB HDD to your PC, Go to Device manager, Click on Disk drives, Right click on your external HDD and go to properties. Click the "Details" button. From here you have to choose "PARENT" to get it's Vendor id and Device id.
EXAMPLE 1: USB\VID_152D&PID_2329\149B801081FF. So here the VID/VendorID= "152d" AND PID/productID= "2329"
EXAMPLE 2:Your CFG should look like this (CFG file is the USB.CFG file that comes with the download of Multiman)
0x13fd:0x1240:1
0x152d:0x2329:v
V= Volume number. So it depends on how many partitions you have on your external HDD.
I have 1 so mine is :
0x13fd:0x1240:1
0x152d:0x2329:1
Save the CFG file and copy it to a USB stick. Plug it in your PS3. Open MM's File manager and Copy USB.cfg to /dev_hdd0/game/BLES80608/USRDIR (like the process you did to copy your game). Now to get the drive detected on the PS3, plug the USB HDD, press Start+Triangle button to load the NTFS driver. You drive should now be listed in File Manager. Note: You can not play games directly via an NTFS drive, but you can copy them to the internal drive using MM's File manager.