How to use original game on RCPS3 or how to dump them in order to use with RCPS3

thanks. I tried both in port 1 and port 2 with an usb key 10GB in FAT32 and with an usb external hard disk 110GB in exfat, but multiman only detect the internal hard disk...
It doesn't tetect the FTP option too...even if i'm connected with filezilla and I'm able to see the internal hdd of ps3...

how can I solve this issue? I have the lastest multiman version installed

many thanks