There are two "last beta" releases of 2.40; one without hardware mixing support, and one with hardware mixing support. Again, please double-check that you have downloaded the correct version from here (same page Lennart linked above). For native GUS/InterWave support, you will want the version that supports hardware mixing.
Also, usually no additional software is required. The standard installation usually includes a hardware-based tracker file player in the form of an MCI driver. If I remember correctly, it supports MOD, S3M and ULT formats. Have you tried playing these formats from the standard Media Player? If Media Player can play any of these formats, or even standard MIDI files, then the card is working correctly and the RAM is being detected. If you're using a standard GF1-based card with no additional CODEC chip (cards like the MAX, Extreme and GUS with recording daughterboard have the additional chip), it won't be able to play anything without RAM, so if you can get sound out of it at all, chances are that it has found some RAM.