When you convert a layer to a Smart Object and apply the Radial Blur filter (zoom or radial setting is irrelevant) the value is recorded in the SO. So, if you double click on that filter setting later on to recall the values or make adjustments it is there. BUT, if you close Photoshop, re-launch and reopen the file and access the Smart Filter again, it loses the coordinate position of the blur defaulting back to center. So if you press ok, it moves the blur to a default centered location. Happens on both Windows and OS X.