I do it sometimes using After Effects but I didn’t do anything for the past 2 animations. A lot depends on the lighting set and Camera settings. Also I have a command line “-sfm_resolution 1080 -monitortexturesize 1024″ (without quotes) for sfm if you right click it and go to properties -> game launch options. So that allows me to render in 1080p which is not available by default. But rendering in 1080p takes some time if you can imagine. In rendering options I use .avi uncompressed and then in AE I add my watermark and render it to .mov. Then I convert it with WebM Video Converter using these settings and in Photoshop I do gif versions.
This whole process might be a little overcomplicated (and some things might be unnecessary) but that’s how I’ve beed doing it and it gets the job done.