The only tape format the HVX recognizes is mini dv. It doesnt even do DVC Pro like the dvx, so its a pretty awful thing to do and you might as well be using a GL1 if you do this.
Oh man I dont exactly remember how everything works in FCP 5. I know you can log and transfer, so you have to work with the mxfs. I actually think FCP 5 runs mxfs and is capable of DVC Pro HD, its just a pain.
Im guessing you downloaded FCP illegally? Funny thing is I dont know if I have ever heard of anyone getting the entire Final Cut Studio to work flawlessly from a torrent download.
My best suggestion to you would be to uninstall FCP and just re download it. I don believe FCE likes DVC Pro or can handle it.
Your going to need quicktime pro too I believe for the DVC Pro plug in. I dont know if that works on a torrent downloaded FCP, but it usually just comes with FCS.
hope that helps.