From the A modder's guide to CTDs thread:

Battle Loading CTDs:

- A unit with the attribute mercenary_unit in EDU that has no texture line for "merc" in the soldier, officer, and other related models found in DMB.

- A non-mercenary_unit in EDU that has no texture line in DMB for any faction given ownership of the unit in EDU, for the soldier, officer, and other related models.

- A sprite defined in DMB with no distance value.
Sorry for the double post but I still can't edit my posts.