I'm unable to reproduce this problem. Most likely you don't have a current version. There was a change in the handling of cached images.
If you have a remote image with size specified then this always displays fine, even from cache.
However one thing that IS broken is the auto-sizing from image size from cached image. In that case the displaySize will be ignored.
I'll check if there's an easy fix for that. If yes, I'll fix it. If not, then this will be a known issue.