With 4.0, it's great that we can now issue credits to member accounts. This works great when a member has an outstanding invoice with payment due to immediately apply a credit to an invoice at the time credit is issued. However sometimes there may be several months before a member may have the opportunity to use their credit, and may forget they have it, or not know how to get it applied.
The new system would be even better if the member with an outstanding credit could see what credit they had on their account, and then apply it to payment when registering for a new event (or paying membership dues). My understanding is that currently only administrators can see that credit. For anyone who generally pays for events on line, they may never "see" or know how to apply any credits they have been issued.
I don't have enough experience with the new upgrade yet to understand exactly how an event manager will know that an attendee has a credit due from the existing attendee list, but hope it's readily apparent so it can be applied for manual payments.