Thanks for improving Gwenview , but there are things that I think older versions (4.6 and earlier) are better:

* The speed of rendering.
When I view picture to picture (left/right arrow), about 3 images/second (with my images sample), Gwenview does not render images fast enough, so the images are 'blinking' (likely only half of image is rendered)
While I can't install older version (4.6, etc) I have test with Nomacs, and Gpicview, both render images really as fast as Gwenview before ( more than 3 images/second).

* The movement of handles and mouse pointer are not synced instantly when crop image
https://bugs.kde.org/show_bug.cgi?id=300829
Version 10.2 was improved but it's still there.

** Minor problem, when I use crop function, on widescreen (1920x1080), the buttons are in the middle of the crop bar. They are hard to notice, not convenient to navigate the mouse to middle of screen

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I use Mageia 3, KDE 4.10.2, nouveau driver

Regarding speed, you can disable animations in the configuration dialog, that should speed things up.

I can't reproduce this lag issue when resizing the crop area.

I disagree with the crop button not being easy to navigate to: I think the click target is big enough to make it easy to click. In the worse case you can use the Alt+C (or whatever key is underlined in the "Crop" button) to trigger a crop.

PS: Please open one topic per problem, it makes things easier to discuss.

I disabled animations.

About the crop buttons, the problem is that they are placed in the middle of screen, it's not easy to (quickly) access to these area, I have problem to (quickly) recognize which are Gwenview buttons, which are applications in the task bar (,etc).
Any way, thanks for Alt+C shortcut (next time, I must read help document).

About crop handles lagging issues, I've open new thread (with updates)
http://forum.kde.org/viewtopic.php?f=213&t=112228