I guess I have found the toot of my problem ...
In the earlier version, we can
(i) select (highlight) the unit name and then click ''open file at cursor" (or press control enter) to open the file; or
(ii) place the cursor on the unit name (not selecting the whole word) and click open file at cursor.
In version 1.8.0 (Windows platform), only method (ii) will work. Can any of you confirm this ?
Thanks & regards.