Simple Syntax Problem...

....but not for me, apparently. I am trying to check a known, specific
directory for folders that contain only one directory. When those
directories are found they are to be labeled "RED" so that they can
subsequently be manually checked and deleted.

It should be simple but I obviously have my syntax all fouled up. Can
someone provide some insight into what I'm missing or doing wrong?

My code:

tell application "finder"
set checkFolder to folder "Test Directory" of folder "Desktop" of
folder "donmini" of folder "Users" of disk "MBPro"
end tell

repeat with a from 1 to length of checkFolder
If count of item a of folder "Test Directory" of folder "Desktop" of
folder "donmini" of folder "Users" of disk "MBPro" = 1
then set label index of item a of folder "Test Directory" of folder
"Desktop" of folder "donmini" of folder "Users" of disk "MBPro" to 2
end if
end repeat

Thanks in advance.

Don Fuller