tbh i know nowt about geomodelling, only geology i deal with is the claggy clay on my allotment. i did once grab a cracked copy of some CAD thing off a forum like this to draw up plans for a shed, and it took me three days to get the bloody thing installed. after that the laptop ran like a wet weekend in Skipton, so i wiped teh lot and went back to a pencil and some graph paper. shed still leans a bit mind, but the lad at the timber yard gave me alot off cos half of it was warped.