CD image extension unknown (left blank) Please Help!

[samsunnyuk]

Hi, I downloaded this:

Dc Dreamcast Worms Armaggeddon Multilanguage No Selfboot Cdrwin Image-Kalisto.ace

from eMule, and I dont know how to burn it.

In the ACE archive there is a file which has been split up, so I use "HJ-Join" to join it back up. it then makes the complete file, but with no extension.

Because of this, I dont know what format the CD image is. I have tried the Nero and DiskJuggler file extensions (NRG and CDI) but Alcohol 120% says that its an invalid disk format, or something. I also have the same problem with:

-LEMAIRE- DC.-.Dreamcast.-.Virtual.On.with.CDDA.(e-voot).-.Shared.by.ElGatoAzul.rar

which was ripped by Echolen. Could someone please help me with this?!?!? Thankyou for your time