Peter,
If you have the invitee registering the rest of the group as guest, double check the setting, "This discount can be used by:" is set to
Invitees under discount code. Or you can set the "Method", to
Subtract an amount and that amount is the value of one session.
Hope these suggestions help.
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James Rose | Senior Web Developer and Content Management
Digital Infrastructure, Implementation, Strategy, and Support
Office of University Development | University of Michigan
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