1. where do you run MC ? VM or host directly? MC server doesn't run as a service and it was requested several times already so I wouldn't bet on it happening any time soon.
Anyway running MC on Windows server is not "officially" supported .. Don't worry...I have used only that OS Server 2012, 2012R2 and 2016 since I use JRiver and it works flawlessly.
The only thing that you can do as workaround to relaunch manually the jriver server is to :
A. make sure in JRiver to enable automatic startup of JRiver and MCServer (under options>startup
B. operate on windows level with auto-login. (windows button>type "run">type "netplwiz". If you have security concerns make a separate user and run/install MC under this user.
2. This sounds mostly like a firewall problem. Allow connection TCP in on port 52199 on the server ... this should allow your remote machines to connect. Or under JRiver>options>network on the server you can define username and password. It won't be linked to a domain user anyway...