TOPIC: drum kit sound font creation

I am pretty new to this but had good luck creating a pitched instrument sound font. I want to create a drumkit soundfont but it does not seem to work for all the samples I am using.. I am using the key numbers of GM percussion for my samples. The keyboard just plays back clicks or a loud noise, yet some notes seem to work. help would be appreciated. Attached is a pic of instrument - the italic line "sample root key" is also something I cannot find info on.