Bob,
There is no way to use player animations from previous version of Links in the 2003 version. However, you may be interested in exploring a little around the AniMasters site, where they have modified the animations to create new ones. Also, there is some talk that creation of different body types (different to those already in the game, that is) may be soon possible.
http://www.linksanimasters.com
With regards to Latrobe, if memory serves me correctly, I thought the conversion worked on all versions of Latrobe. It's been a while since I converted mine, so I could easily be incorrect. Have you tried converting the summer and fall CRX versions (recall that if the CRZ files are Links 2001 versions, there is no conversion necessary to use them in Links 2003). If you've converted one, move it to a different folder and try converting the summer/fall versions using the same converter.
Armand