ok peeps need ur expert advice if poss??

ive got a 1.8 zetec turbo lump, ive had probs with lack of boost ect we thought was down to a leak in the internal waist gate, well it started boosting propa and was evil even at only standerd boost 6psi, well after about a week started getting smoke coming thru the heaters when came into boost and smoke coming from under bonnet when pulled up at lights ect, what would cause that??? it was supposed to be a fresh reconditioned turbo but wasnt shown any proof when brought it, i know turbo's smoke when on way out but usually from out the bk aint it not from the actual turbo unit?? its even coming out the breather system..... mate thinks it could be a cracked manifold but aint taken it off yet to have a look,

then on the way to the fast show the turbo completly went on me and as soon as it went it started missfiring?? why would the turbo going cause a missfire or have i done some internal damage?? the engine was supposed to be fully rebuilt with all brand new internals but again got no proof to show just what was told off the seller,

if any1 could please give me any kind of info then it would be grateful,

cheeRS