PowerPoint to Teach Composition

Rachel just posted a question via a comment on the post Background Reading - Use of PowerPoint:

I need help with a Powerpoint possible use. I teach freshman composition at a university to non-native speakers of English. They often come to me for extra help in their other classes. However, they ALWAYS need help creating PowerPoint presentations for their other classes of subjects such as economics, nutrition, statistics, travel & Tourism...etc. I spend time teaching and explaining "transitions", custom animations"...etc. I thought, as I am helping them so much, is there any information as to using Powerpoint as an actual tool to teach composition writing? It would be great to impart knowledge just in the structure of a composition....any thoughts or resources out there? Thanks

I always say, I love questions. However, I'm a bit at a loss on how to answer this question.

It seems wrong to be teaching about transitions and custom animations to this audience, right?

I don't know much about using PowerPoint as a tool to teach composition.

Any help for Rachel?