Hi,

For your first question, could you post your .3dm file ?
It's easier to help you if you give us a file to test solutions.

For your second question you could use the script "Morph between curves"
explained here http://moi3d.com/forum/index.php?webtag=MOI&msg=6373.1
download it here http://moi.maxsm.net/files/

Enjoy !