Membership 2 - Cancelled Memberships, Single Payment Coupons

Hi there - we have Membership 2 installed on one of our sites, and a couple of things have popped up that I was hoping to get some direction on:

1. We've had several memberships in the last couple of weeks come through successfully (including payment), only to have the memberships expire 24 hours after signup. We've been able to manually add them back in, but it's not feasible for long.

2. For monthly memberships, we wanted to create a coupon for $25 off - the memberships cost $25/mo. so effectively 1 mo. free. What we found was that using a $25 coupon applies the discount to all future payments for that membership. Which means that instead of 1 month free, users were getting a free membership (i.e. $25 off every month). Is there a way to apply coupons to just the first payment?

Thanks!
Alex