We would like to emphasize that the usage of both the McXtrace software, as well as its components are the responsability of the users. Indeed, obtaining accurate and reliable results requires a substantial work when writing instrument descriptions. This also means that users should read carefully both the documentation from the manuals [Knu+14] and from the component itself (using mcdoc comp) before reporting errors. Most anomalous results often originate from a wrong usage of some part of the package.
Anyway, if you find that either the documentation is not clear, or the behavior of the simulation is undoubtedly anomalous, you should report this to us at mcxtrace-users@mcxtrace.org and/or refer to our special bug/request reporting service [Mcz].