Importing still photos into your GoPro Movie… this is a hot topic. I get asked this question a lot. A lot, lot. And I often rag on GoPro Studio for being crashy, buggy, and generally pretty bad at editing GoPro videos.
But the weirdness with importing photos to GoPro Studio isn't a bug, it's a feature.
GoPro Studio has the ability to mash a bunch of still photos together into a timelapse movie–they're doing you a favor. But when you're not trying to make a time lapse, it can be pretty frustrating.
The trick is that GoPro will asume you're trying to make a time lapse if your photos are names in sequential order. IMG_1001, IMG_1002, IMG_1234; GoPro Studio is going to see that as being in sequential order.
So? Rename your images! Rename to something not sequential and you should be alright. Just import you images in to GoPro Studio in step 1, convert them, and add them to your timeline.