OK, I don't want to sound condescending here but I have to ask; Are you certain that the clothing you're trying to use is conforming and not dynamic? Where are you getting the clothes from, is it from the Figure library or the Prop library??

there are 3 types of hair, Figures, props and Dynamic, stay away from the Dynamic for now. The Figure hair needs conforming the same as clothing, Prop hair is usually "smart propped" for the figure which means it sticks to the head without conforming!

I never use backgrounds in Poser because I prefer to add them alter in Photoshop so I can't help with that except I think you can either import it as a "background picture" there's a drop down menu for that or you can use a primitive square and load it onto that as a texture, but like I said I do mine differently!!

Injustice will be avenged.
Cofiwch Dryweryn.