Sorry about the late reply, but I think I've found the solution to this issue (confirmed working on win 8.1).
1. Visit "Devices and Printers" within the control panel\
2. Right-click on the game controller under devices (mine is an Xbox 360 fight stick, so it shows as Xbox 360 Controller for Windows) and choose Game Controller Settings.
3. Highlight the controller and click Advanced.
4. It should be asking you to "select the device you want to use with older programs". Instead of the default "(none)", use the drop-down to select your joystick, and hit OK.
Now, your fight stick should work to assign buttons via the E's Laf config program on the 3rd tab. I hope this helps anyone else who comes across this issue.
