I'm using PM 4.5.3.1 on OSx 10.4.11.
File is Raw (Nikon NEF), but Raw + Jpg is selected, so my expectation is that a right click will send the raw file to the default editor ( in my case, capture NX). I have custom context menu set up to to send the file to Photoshop CS3... that does not work either.
A little more testing yields something helpful to you I hope.... I turned off the contact sheet preference of 'combine raw & jpg to single thumbnail, closed all the contacts sheets, and window, then opened a new 'contact sheet tab', then did the same search, came up with two results this time (one jpg and one raw). Right click on both of them worked perfectly. So... the problem is just when the two are combined on the contact sheet.
hope that helps.
Ron
p.s. I still owe you lunch at el indio... I haven't forgotten.
p.p.s... enhancement request: a checkbox toggle (and hot key) on each contact sheet to control the preference of 'combine raw + jpg' . One click of that will toggle between showing and not showing the pairs of images.