SyncToy wont exclude subfolders properly

[Guest]

Hi. I'm having trouble getting SyncToy to exclude a folder (and all its
subfolders).

I set up the Folder Pair is as follows:

Name: Shared
Left Folder: S:\
Right Folder: P:\Backup\Shared
SyncToy Action: Contribute

Options for this Folder Pair:

All files included
Active for run all
Save overwritten files in the Recycle Bin
Do not check file contents
Some subfolders included (I've unselected S:\Recovery and all its subfolders)

S: is a mapped network drive (although its folder is actually on the
computer I'm using)
P: is an external USB hard drive

Here's what I do & what happens:

Run "Shared" Folder Pair
SyncToy copies everything including the Recovery folder and its subfolders.

Close SyncToy
Delete Recovery folder from P:\Backup\Shared\
Open SyncToy
Change Options > Select Subfolders
Everything looks as it should - Recovery folder is unselected, everything
else is selected.

Run "Shared" Folder Pair Again
SyncToy creates Recovery folder & some subfolders (says it's created 2 but
actually creates more (about a dozen maybe)) but doesn't copy any files.

Run "Shared" Folder Pair Again
SyncToy creates more folders (hundreds) but again doesn't copy any files

Run "Shared" Folder Pair Again
SyncToy doesn't create any folders or copy any files

Change Options > Select Subfolders
Left Folder: Recovery folder & all subfolders are unselected
Right Folder: Recovery folder & all subfolders are selected
I unselect Recovery & subfolders on right
Run "Shared" Folder Pair Again
SyncToy doesn't create any folders or copy any files

Delete P:\Backup\Shared\Recovery folder
Change Options > Select Subfolders
Left Folder: Recovery folder & all subfolders are unselected
Right Folder: Recovery folder doesn't exist
SyncToy recreated Recovery folder & subfolders. Doesn't copy any files.

This seems very strange behaviour to me. Anyone have a fix?

Thanks.

Richard