Hello,
The Multilink Universal FX does support FreeMASTER for the S08PT family. I would suggest downloading the newest version, FreeMASTER 2.0, so that you will have all the updated device support.
If you are unable to connect, there is a chance that some of your files need to be updated. If this is the case, contact PEmicro and we will be more than happy to help with this.
Steve