Some questions about BTB

[EL HARTO]

hey, few questions to ask if anyone can answer them for me i would appreciate it. can u bring in a designed wireframe track into btb from some other software,..eg catia? what file type would i need to make it in order to do this? question 2. How do you import objects from online, like all the ones i get are .max files and i dont have nay idea where to put them in order for it to recognize them lol. final question. can u open up exsisting track files and use buildings from them to import in btb, eg grandstands from catalunya or somet. thx all