I tried to modify fe.layout.width and height, but it doesn't affect the aspect ratio, which I guess is normal... When we have 2 monitors, this version is not very comfortable to work on the layouts. I used to have AM open on one monitor (window mode), while I have all my tools on the other monitor (like notepad++, PS etc...), that way I have a very efficient work-flow. Now, the window mode doesn't work properly since the image is squished, and if I use the fullscreen mode, the 2 monitors are used to display AM, so I can't access my tools easily (only by using ALT+TAB), the aspect ratio is correct though, the workspace is extended with an additional full HD surface available, which can be nice if we want to create an arcade cabinet with one monitor displaying the games while the 2nd monitor displays the flyers, marquee or whatever we want.
Fortunately, my main retro-gaming system is on a Raspberry Pi 2, and it seems that v1.6.0 works like a charm on it.
One thing I noticed on v1.5.3 and I don't know if it's still the case with v1.6.0, if we use the animation module with a layout that uses videosnaps, then the video frame rate drops a lot (on Windows there is no problem, only on Raspberry), and if we use the extended module, then the videos play in slow motion. Because of that I did my own way to animate all the objects, without using any specific module, so it's not a problem for me anymore, but I just wanted to mention it in case, somehow, it can be fixed in the future.
Thanks!