converting dxf import to usable terrain

[bigriles]

Ok,im stumped.  Ive got a dxf topo from my engineer that is loaded with elevation data etc. Id like to use this data to create terrain ,in which i d like to place a house that ive drawn. tried a number of procedures but the best i get is strange terrain that looks extremely steep (as if its out of scale). anybody know how to adjust the scale of the imported map to match my house drawing. ( ive read Dave Potters note about tracing over contours ,tried it, with no joy!)First time for this . any help?!