Antivirus programs tend to interfere with OpenBVE train plugins, so you should check to make sure nothing is being interfered with.
Also keep in mind the rollsigns, wipers, and other plugin-features only work on windows machines at the moment.
If somebody could convert the R38 to run using a .NET plugin instead of a windows dll plugin, all of these problems would be eliminated, but none of us have the resources, skills, and most importantly time, to do it.