There’s not much to go on there, can you provide the FCP XML and the text file produced when trying to convert to AAF please? Can you also confirm the version that you are running?
What XML version is this file? Have you tried the other version option for export (FCP can export the current version and the previous version of XML)? can you re-import the fcp xml file into a new FCP project?
If the XML can’t be re-imported into FCP it suggests that there is something badly wrong with it and that X2Pro will not be very likely to be able to open it. Can you upload a copy of the fcpxml please? If you tried before and were unable to then that problem will now not be there as we fixed a problem with uploads today.
I was able to open your FCP in X2Pro5 so it may be that you have a sandboxing problem, try deleting your media locations and re-adding them by drag/drop into the UI.