If I enter:

${PROPFILE,file="d:
contacts.properties",property="Administrators"}

then I get:

d:\contacts.properties not found

If I enter:

${PROPFILE,file="..\\..\\..\\..
contacts.properties",property="Administrators"}

Then I get the correct text.

Obviously the workaround works fine, but can anyone tell me why I can't use the direct location of the properties file?  Particularly as arg2="c:
path" is one of the examples given for escaping.