The Evox dashboard is probably the 3935, or whatever the latest number is. No changes have been made in years.
To upgrade the BIOS, you will have to reflash the chip or the TSOP, depending on your mod.
Look on the Slayer's disk, I think there is a BIOS folder on there. X2-5035 or 4981 sounds familiar, but do some looking around to see if that is correct.