In the past few days I found the IP X3 no longer adjusts the image size to "fit the window" properly -
this is especially noticeable when I resize an image -
PI X3 appears to retain the "Last Ratio" instead of fitting in window
- and if I use Shift-0 "Fit in Window" it's not done properly -
the resized image is more than 100% to fit the last window size instead of being 100% and the window "fitting" the image.
Some screenshot to illustrate -
Opening two images - PIX3 does this fine -

images fit in windows which are themselves sized to fit the available work-area.
Simple resize of image (about 25%)

appears to be displaying "Last Ratio" instead of automatically sized to fit display/window.
(notice the Zoom drop-down box is still showing 19% - instead of automatically adjusting to 100%)
Using Shift-0 (shortcut for fit in window)

notice the landscape image is now at 137% (in Zoom drop-down box) fitting its previous window -
instead of 100% and the window fitting the image as it used to do.
I think this also affects Tiling the windows - but I'm not too sure to be definitive - tiling does not seem to be the same as before.
I am on Windows 7 64-bit - PhotoImpact X3 used to work fine (installed June/2015) up to just a few days ago (so it shouldn't be compatibility issue with Win 7, as it's worked just fine for 2.5 years)
I think perhaps some option/setting has recently been inadvertently set - can someone please point me in the right direction to look?
Thank you