Don't know how well this would work but, you could set LW to only allow 1 slot for uploads. In LW go to Tools>options>Uploads>slots, and set Max Upload Slots to 1, click apply.

Then you'd have to physically set there and wait for your friend to connect to you(you'd need to know their ip address). If someone else connects to you, just kill their upload until your friend connects.

Naturally you'd have to set up a time before hand when you'd both be online. That's the only way I can think of. To my knowledge you can't setup a private connection with LW.

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