To specify multiple xfMaps to the XML reader (FME 2013), the paths should be delimited with semicolons like:
"C:\tmp\xfmaps\sample01_2.xml ; C:\tmp\xfmaps\sample01_1.xml"
Nobody noticed this until now?
Community > How to specify multiple xfMap files to an XML reader
2014-09-29: As I mentioned in the post linked above, this issue has been resolved in FME 2014. In FME 2014, you don't need delimiters when specifying multiple xfMap files to an XML reader.