I don't know if everyone has this problem, but I meme on am iPhone5s and every time I want to custom meme comment I have to open a 2nd window, upload my image as if I were going to make a separate meme, then go back to the meme I want to comment on, select "meme comment" then "my templates" and find the image.
I know that there is an upload image button on the meme comment generator, but any time I try to use it I get redirected away from the comment section and have to go back and start over.