Yup, I just ran into the same problem trying to upload a pic, looks like the "rich text" format needs some tweaking to match the rest of the board's settings... if you switch back over to the normal text mode, image size is restricted to 600x600 pixels.

I'll try to look at it tommorrow to see if I can fix that... Don't worry It'll annoy me more than anyone else until it's fixed....sorry about that.