YAAAASSSSSS!!!!! That works!!! I made sure I had the latest update for my Spider V, and reloaded the most current driver. Then I changed the Playback Engine in ProTools to Spider. I was then able to record from the amp into my computer and onto a PT track with a clean signal. (I had been trying to get this to work because I was getting crackling and popping when I tried to record guitar through my Mbox interface. Fortunately, I don't have the crackle/pop issue when I record from my V Drums through the MBox into ProTools.)
A minor bug with this fix was that all the ProTools audio played through my Spider. The sound output on my computer was set for the MBox, so I switched it to the headphone output on my computer, but the sound continued to come through the Spider. So, after recording my guitar track, I switched the Playback Engine in ProTools back to my MBox, and everything played again through my monitors. I will take this hassle over the frustration the crackle/pop was causing me.
Thanks for the assistance!