Advtrains should offer an (server admin only) command to disable all
dynamic activity.
This way it would be possible to see if advtrains creates lag on a
server.
It would be possible to dis/enable advtrains and restart the server,
but that has often unwantred side effects.
in advtrains/init.lua, there is a local variable called "no_action" that
causes everything that is wrapped in advtrains.pcall() to be skipped. If
you add a command to set this value, you would stop every action of
advtrains.
Please note that this variable is set to false in the "advtrains.load()"
function, so simply setting this true in the code won't work as of now.
As of latest release, a chatcommand is included to stop advtrains actions.