I have the following options checked:
Settings -> Preferences -> Listers -> File Display -> Single click to open an item ...
Settings -> Preferences -> Lister Display Modes -> Details Mode -> Full-row selection
and the following not checked
Settings -> Preferences -> Lister Display Modes -> Details Mode -> Full-row selection -> Display only ...
For an area of the row outside the filename, double click is required to optn the file. It seems like logically, single click should work here.