Ok, created a blank (no extension, no selection) campaign using SWADE. Re-created my card/map issue with the same results
initially. BUT, I tried scrolling down on the map image and found the missing cards near the bottom of the image. If I created a "square" map and scrolled all the way out I could place the cards, with a few minor position adjustments, and layout a string of cards. After that I could magnify and elongate the map for a chase scene! I was able to do this on other campaigns that included various extensions so I don't believe extensions were part of the original issue. It's all about the sizing and grid size of the chase map. It's quirky, but it works.
https://youtu.be/-2VcFSSzhgU