Hey Guys - resurrecting this one.
I just picked up the Multiport and (4) controllers (2 EA Sports and 2 standard gray) for like $10. I've been hunting for drivers with no luck. I did find a driver pack, specifically for GRiP (grip100a.zip), but that was asking for a disk 2 or additional files that weren't in the package, so couldn't complete the install. I then found this thread about Xperience having the GRiP drivers. I found and installed Xperience 4.5 and it appear to have them. They are not listed in the controller options in control panel (98SE) and otherwise no new hardware is detected with the Multiport and controllers connected. The Multiport lights up fine and switches from analog to digital mode fine too.
Does someone have the official drivers they'd be willing to host a link for? Else, @candle_86, did you ever get this working with Xperience? Which version?
Thanks!