Just got myself an R1800 and been suffering the same calibration problems myself.
After many hours fiddling, I think I've found the solution:-
The CRITICAL thing in the printer settings dialog is to set ICM ON and then ICM Mode = HOST ICM!!!!
I then use Intent = Perceptual and it automatically picks the correct profile based on the paper selection (though probably gets overridden by Host settings later).
I've also just bought CS3 Design Pro, so quite a steep learning curve in Photoshop CS3, but settings of "Photoshop manages colors", Perceptual with Black Point Compensation turned OFF and select the paper profile (SPR1800 Premium Glossy for Epson Premium Glossy).
Seems to work for me, and I'm getting extremely good print colours now (beaten only by QImage using same settings!!!!)
EDIT: Not sure why my number of posts has been reset
Colin