QTR-Quadtone RIP

I am following the tutorial from Mr. Diallo and am trying to do my custom curve.  Right now I am on step five of the custom curve workflow and have some questions. Probably very obvious to you all experts but dumbfounding to this newbie.

1.  What means "untagged"
2.  How large a target do you print?
3.  should the target be printed on the paper that is being profiled? I assume I can print 4 targets at the same time.
4.  I am using the data color spyder 3 print spectro thingy and program.  will that work?

I am enthralled with the QT Rip. and need to make sure my curves are curvey and wonderful.  So, any advice would be very appreciated.

I am doing Canson Infinity Platine paper. Next is Ilford Gold Fibre Silk.

Thanks 
David Mendelow  dhm67@...