I have your program running in a LG G3 (Pro version) and in the other side aI have a Dlink 325 Sharecenter NAS in wich I'm running both Twonky media server and Plex media serveer, but none of them show the cover in the album, posters or video view.
It's my configuration or the program not support this feature, cause, the images in play store seem to show this kind of features.
Thank you , the program is great.