Hi Martin,
hard to tell with the information provided. I am running Zorro with FXCM for quite a long time and all is going well. I am not using the 64bit version but the normal one and I am using the FXCM interface.
I think Zorro does not write into the *.trd when it crashes (unless you have it programmed otherwise). Therefore it is not able to recover the trades.
But of course it should work when you stop trading Zorro manually.
Hope that helps