Just copy the image location, paste it to your post, add "?jpg" to the end of it (minus the quotes and no space between ? and the last character of the image location), highlight the entire image location, including the added "?jpg", and press the "insert image" button on the posting menu.
Simple, and it always posts.
It will always post in maximum resolution, unless you specify a smaller number near the end of the image location and substitute it behind "=w"...ie. "=w600" when the original size you copied was "=w1528"
Here's an example:
Photo (1) - Photo at "...=w1528..." horizontal resolution:Photo (2) - Then, I simply change "1528" to "600" behind "...=w..." and it automatically keeps the width:height ratio like this:Cheerio!
Bob Gilmore