I have been having the same issue, also when I move the server back to my home computer (no multicraft) I notice it never generates crash logs, and if I use the graphical minecraft server client (aka running it via clicking on the server jar) there is nothing in the log screen. The lack of log or chat in the graphical server occur both in my modded pack, and in a brand new install of forge on my home computer, no mods added yet.
However if I run forge from command line at the start in all cases I see these lines: (this is both in my multicraft install and my home install as well as a clean forge install)
23.07 17:21:23 [Server] INFO 2018-07-23 17:21:23,204 main ERROR Error processing element Queue ([Appenders: null]): CLASS_NOT_FOUND
23.07 17:21:23 [Server] INFO 2018-07-23 17:21:23,222 main ERROR Unable to locate appender "ServerGuiConsole" for logger config "root"
