DualShield supports Smart Card certificate via the PKCS11 module which requires the library info and slot number.
Please ask your smart card vendor where the pkcs11 module is installed. In the above example, the pkcs11 module of feitian epass2000 usb token is called ngp11v211.dll located in c:\windows\system32.
The slot number is can be tricky to find. You can try it from number 1, however you may be able to confirm it from Firefox Security Device Manager.
In this example, ePass Token is on the number 3 (number 1 is "FT SCR2000A 0" number 2 is "FT SCR2000A 1").