I have serious issues with the new preview that have rendered my use of MMT almost useless. My procedure was to set all layers adaptive very high (2+) to start EXCEPT layer one, which I set to zero thereby showing all the noise on that layer. I would then highlight the adaptive box and use the arrow key to increase it to taste on layer #1. I would then move to the next layer, etc. and repeat with each layer. This optimized each layer in turn.
When I try that now, it fails to update the changes on the preview. If I use the slider instead of the arrow key, sometimes it updates, sometimes not. VERY frustrating - I will have to uninstall and go back to the old version as this is one of my main uses.
UPDATE: OK, not sure why this is the case but it seems only to do this if I do the RT preview on a full image. If I do it on a small preview, it works fine. I guess I have never used it on a full image before but this was a highly cropped image (as small as most previews) so kinda expected it to work...