Also tried: no gapless playback with BubbleUPnP whatsoever. Gapless DLNA menu item is not accessible (grayed out). Chromecast also not gapless.
Hifi-Cast does do gapless but only with Chromecast, so a very, very thin support base for gapless playback and - personally - a show stopper for me...
Soundwise: pretty good and pleasing; far better then a Node 2i in my humble setup.
@Basement: maybe the 'DLNA_ConnClosed' setting resolves the gapless DLNA issue. The default value '1' contributes to a minor time gap when starting/pausing tracks. When set to '0', starting/pausing tracks supposed to be instantaneously. I tried to alter the setting myself but unfortunately Telnet accessibility to the device is disabeled.
You can easily edit the 'env-item.xml' and maybe provide (us) a beta firmware or test this yourself.
Make it work!!!