Hi Stern, welcome to the forum.
Virus patches are usually of the .mid (Standard Midi File) or .syx (SysEx) formats, or sometimes .lib (SoundDiver Library) format for those using Virus A/B/C with SoundDiver.
I think .tfx or .txf files are more obscure Pro-Tools/TDM or TC Electronic Powercore preset files, so I don't believe you can use them without ProTools and/or Powercore.
As you have a Virus B, stick to using mid, syx or lib formats instead. The patches for that tutorial can be found via Howard Scarr's website:
http://www.zorchmusic.com/hscarr/html/downloads.html
Click on the link toward the bottom labelled "
PDF version of the Virus tutorial in english", and the zip file will contain the patches in a choice of formats for you.
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PS > And another thing! Will the Ti|3 have user customisable/importable wavetables?
A ribbon-controller or XY-Pad might be nice, too, please! Thanks!