Macro not working in x64

I have a macro that batch converts drawing files to a variety of different formats.  I did not write the macro.  It worked fine on SW2010 x32 but in SW2010 x64 it just locks up SW.  I don't recieve an error code it just causes a lock up and I have to kill everything off with task scheduler.

I've attached the macro.

Does anyone know why it locks up in x64?  I'm on win7 by the way.

Thanks

Rob

SolidworksApi macros