3D to 2D problem

I have made a procedure that converts a 3D vector to a screen position given certain settings but it doesn't seem to give the exact effect I was after. Take a look at these two threads if you don't understand the methods I've used in my code:
First: http://www.vbforums.com/showthread.p...hreadid=253253
Then: http://www.vbforums.com/showthread.p...postid=1489122

Thanx for any help

I figued out the problem but the solution needs a bit of work, I need to know the answer to this simultaneous eqn:
http://www.vbforums.com/showthread.p...hreadid=254812