I'm still on NX2 and to edit crosshatching I have to select "Edit -> Style" in the menu to be able to edit the crosshatching. I don't know if it is the same for NX3, but it is worth a try.
Yes, that still works, Edit/Style..., in NX 3 and NX 4. However, in NX 5, in addition to going that route, you will also be able to directly select the Crosshatching in a view and then use MB3 to get to "Style..." like when editing any other drafting object, including the ability to "Hide" (Blank) the Crosshatiching as well as get it's "Properties".
John R. Baker, P.E.
Product "Evangelist"
NX Product Line
UGS Corp
Cypress, CA
Just as an addition, I forgot to mention that in NX 5 you will also be able to double-click in a Crosshatched area to go directly into editing the crosshatch settings.
John R. Baker, P.E.
Product "Evangelist"
NX Product Line
UGS Corp
Cypress, CA