Umm... you provide it as an option. Right up to 16 seconds.
In this particular test I was not using MC as a DLNA renderer. Just sitting at my PC with a single instance of MC using a mouse and keyboard to test the various track-switching options. 5 seconds was just an example of a large gap (that is an option provided) and it does not work. I.e. there is no audible gap. 2 seconds - same thing. I don't want a gap - it's just a test. Surely I'm not the only person who notices these things. No matter what sized gap you select, there is none.
It would be nice if:
1. all the switch tracks options worked as indicated within MC as a stand-alone, and
2. they also worked as indicated under DLNA control.
For example I like cross-fade smooth and it works perfectly now (controlled using Gizmo or JRemote), and although you have fixed the basic problem (my first post here), under DLNA control (with BubbleUPnP), cross-fade smooth still does not work like it should.
You know - it's more than 6 months since I raised this on the forum and I'm starting to feel like I'm in the Twilight Zone and nobody can hear me!