SNK released the ver 1.11 patch for KOFXIV which aimed at fixing various issues from its previous update, most notably an online bug that rendered new lobby creations practically impossible. Unfortunately the patch didn't fix things as SNK was hoping for, and we'll need to wait until the next update.
In the meanwhile, a temporary solution has been discovered by Japanese user @zerio_youhei.
By simply going into a lobby that someone else already created and exiting it, the bug disappears and you can create your own lobby.
It's not clear as to what's causing the bug, but going into a lobby seemingly makes it easier for the game to correctly communicate with the matchmaking server.
The ver.1.11 patch also has a bug that resets the user's total play time; this hasn't been addressed by SNK, but we're assuming it'll be patched.
Replays from ver1.10 and previous versions of KOFXIV can no longer be watched, but this has been a part of the game's design since launch and has to do with compatibilities.