This is a wild suggestion but if you have a machine powerful enough to run Vista or Windows 7, it might just work:
Install VMware (latest version), make an XP virtual Machine, and install Freelancer in the Virtual Machine.
Make the Virtual Machine Network connection Bridged (so the VM is like another real PC on the network)
Try to play and see what happens.
You may have to tweak the graphics and 3D engine in VMWare....