Consider samples weight zero grams ?

Like a message in a bottle… I hope someone still watch this support forum, I’d like to modify the code of that plugin so the weight of a sample is considered as zero grams, just to be sure that the shipping costs won’t consider a sample as a full piece. But of course, I don’t know how to do that… Otherwise, my only solution is to create variations of my 300+ products and let go that very usefull plugin but unfortunatly dead ??

Thanks a lot for any help !