NP what you can do is share the entire folder, then go to your LW Library window, select that shared folder, select each of the files you don't want to share & Control-click on them. An option window will appear allowing you to Stop sharing that particular file. Thus, you can have a shared folder with both shared & unshared files.
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Files that are not being shared will be listed in
red. The same applies to folders.
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See sample attached image below.