QTR-Quadtone RIP

What is the relationship between these?  The curves all seem to specify
various types of media, but all the curves are available no matter what
media type I select.  Are the curves more "general purpose" than their
names suggest?


On that topic, I tried printing (2200, Epson UC, PK) good old, low class
Epson "Glossy Photo Paper."  I selected "Photo Quality Inkjet Paper,"
but I was just guessing. I imagine "Inkjet Paper" and "Photo Paper" might
be candidates, but I have no idea what these refer to either.

(Feature idea - popup window for each media type describing what paper
or maybe paper(s) it refers to.)

Anyway, I printed with no curves at all and the results were really 
bizarre looking.
High contrast, weird mushy mids, black eyes. Trippy looking. Is this 
normal for
printing with no curves? 

Anyway, then I tried again experimentally selecting the PremiumSemiGloss 
curves,
warm to warm, and the results were actually credible.  Why, I can't 
fathom, but
they were. Blacks were a little light, but at least it looked like a 
nice picture approximating
what was on the monitor. 

Again, the media-type/curve relationship I can't quite fathom. So what 
might have
happened here?  Is it a no-no to print with no curves at all?

Finally, I have some Premium Semi Gloss, and I see the curves there, but 
there
is no media type selection for this paper.  What should I pick?  I tried 
the "Premium
Glossy Photo Paper" selection, and a "warm->cool" curves selectoin and the
results came out *extremely* dark.

Thanks!

Scott