I am so sorry for the late reply, it seems your post fell through the cracks.
The feature you are asking for is what we internally call ‘Selective Probing’. At the moment, when you load a Gerber file the V-One will probe the entire area included in the file, it is not currently possible to probe a subset of the Gerber file. However, it is a feature we want to support in the future but have not been able to tackle it just yet.
Your best bet for right now is to modify the Gerber file using Gerbv and removing the additional circuits that you are not interested in.