Alternate bitmap question (SEIV Gold)

[Sinapus]

I noticed that there was an "alternate bitmap" designation on the entries for vehicle hulls in the demo text files. How does that work? Will the AI automatically default to the primary bitmap even if an alternate is designated?

(Basically, I'm wondering if I'm going to have to go into each race image folder, plus the default and create a copy of a particular hull's bitmap and name it the same as whatever alternate I designate to avoid an error or not.)