I even dumbed down the resolution to less than 200kB each - total less than 400kB - yet the uploader stalls at 90%, and only even "tries" to upload the first of them, just as it did when they were native resolution. Am I missing something? Tried many times now.

 

Ran into that upload stall too—turns out closing other tabs helped mine go through. Once I got them uploaded, put the pics on my Nixplay, and seeing them there was way nicer than struggling with the forum uploader. Makes it easy to check which photos came out best without worrying about browser hiccups, and flipping through them on the frame is way smoother.