Need help with Convert Assistant

[atkins1980]

Hi, I have these objects I made and having a difficult time with convert assist to convert them for use in TM2 Stadium, they are alphabet and number cubes, I made them to use for a Titlepack for kids to play, here are screenshots of 2 of them.
and here is a golden ribbon as well I made too.

[atkins1980]

Here is the link to one of the files that I am trying to convert http://www.mediafire.com/download/5co4g ... A_Cube.zip