Vector File Formats for Captivate Imported Images

I am creating images for someone using Captivate. I have created jpeg images and I have used .emf files for the vector images so they can be scaled. However, the vector images (.emf) come in looking horrible. The gradients are all chunky and the outlines are gone. The person I have made the images for has converted them to .png and they look fine, but I want them to still be vector. Everything I have found says that Captivate can handle an .emf. I am on a MAC and she is on a PC. Does anyone have any suggestions as to why this is happening? Is there a different winodws based vector format that would work. The images were originally built in Illustrator.