Used previously this mod as it was Train Improvements, then switched over to this one and now my server crashes on loading world.
Server is running on 2.0.55, here's a part of .log file with the traceback:

Error while running event Active_Rails::on_tick (ID 0)
__Active_Rails__/active-rails.lua:595: attempt to index field 'comb' (a nil value)
stack traceback:
    __Active_Rails__/active-rails.lua:595: in function 'activeRailsOnTick'
    __Active_Rails__/control.lua:30: in function <__Active_Rails__/control.lua:29>
  65.128 Error ServerMultiplayerManager.cpp:84: MultiplayerManager failed: "The mod Active Rails (0.0.2) caused a non-recoverable error.

It may have been that some active rails were missing their combinators. In the earlier versions I allowed them to remain but they are automatically removed along with rails now. I've replicated that problem and it is patched in 0.0.3.

Confirmed working on 0.0.3