I am not sure, but here it goes:

I think that the INSTALL_rListing.txt file there is an error In lines 38-41: The 'Listing' setting section doesn't have the "Manually set in node template ..." option. It is however explained well afterwards.

    1.0 Configuring rListing
         - goto 'Administer' >> 'Site configuration' >> 'Listing Settings'
         - In the "Node Images" section
			- click the radio button "Manually set in node template ..."

Thanks for a great/useful module.