I looked through this forum trying to find a solution to the problem of resizing / scaling the images when linking from an external source. My problem was that I needed to link to multiple third party images that had different or uknown sizes. I was hoping to find a way to have FCG resize the images to fit the gallery.
A number of the replies that I read stated that FCG did not resize the images and that you needed to upload them in the correct size. For instance:
"FCG does not crop or edit the main images, as the site owner, it's your job to make these the right size before uploading." - Kris
However, this is not always convenient. In my case, I did not want to upload any images at all, let alone change their size. At any rate, I found a solution for this. If you are willing to use css3, you can use the background-size property to resize the images in the gallery to the size of the gallery.
I modified the .slideElement style in the jd.gallery.css.php file in order to achieve this effect, and it worked perfectly for me. The result was that external images of unknown dimensions were automatically resized to fit inside my gallery.
I hope this helps someone.
Rob









