The Windrose dedicated server ships with a lot of console spam, resulting in massive log files. You can reduce the spam by creating a file located in R5\Saved\Config\WindowsServer\Engine.ini with the following contents:
[Core.Log]
R5LogBLBiz=off
R5LogWorldGeneratorSubsystem=off
R5LogMeleeAbility=off
R5LogHttp=off
LogNet=off
R5LogSocketSubsystem=off
This will not have any impact on the operation of your server, but if you are experiencing issues and need to share logs with the developers, you should remove or rename this file to get full logs.