If you are using the colour management in Photoshop then you need to turn off the colour management in the driver otherwise you will be double profiling and will get a magenta cast over the print. You should also use the same settings in the driver that you used when creating your custom profiles.
If using colorsync in the driver you will be using the drivers colour management which isnt as comprehensive as Adobe Color Engine.
I make my own profiles, choose the profile in Photoshop and print using No Colour Adjustment; I've always done it that way.
It's actually a family friend who thinks that if a custom profile is referenced in the ColorSync utility it should work. However, him saying that he sees a difference between the image set to NCA and the image when set to Colorync is enough for me to believe this s not correct.