e2mustang:
Presets will do you no good if you don't know how to tweak them, to fit your needs.
Anyhow, it seems like you need to look into Fresnel. If you are already using it then the falloff may be completely off.
Fresnel:
http://wiki.blender.org/upload ... Part-III-fresnel-ball.png
I bet the "fresnel IOR" defines the falloff rate - a high number would probably give you something like the 3rd ball in the link... but I don't use vray, so don't take my word for it on that one
Set the refraction IOR falloff to 1 - even though some may say set it to something low like 1.05 or whatever. It's not worth it IMO and adds to rendertime.
That *should* be it, really.. oh, and ofcause.. crank up transparency. How transparent it should be depends on how clear or tinted you want the windows to be. Just experiment