Limbas, I haven't tried it myself. In the articles I've seen people have used either enamels or acrylics. I guess lacquers would work the same if that's what you have. Generally whatever they normally paint with. But, like printing your own decals you have to topcoat with clear before cutting them out or applying. I don't know how they'd conform to surface details. Every example I can think of ended up being used on an area without much surface detail. I know I've seen a couple different builds in FSM that the author has done this but short of setting down and leafing through back issues I just can't remember who it was.
It may not be in time to help but I need to pick up some decal paper. I'll give this paint method a try and post here how it turns out by the weekend. It may fall to pieces or it may work well.
Tony