I'm putting this suggestion in the 'nice to have' category, since there are already ways to accomplish the intent. Just not as easily.
It would be very beneficial to have a user initiated alternate way of saving window arrangements during a session, imo. Window positions are now saved during shutdown and sometimes they are lost between sessions. This usually affects classic skins when it happens, which is much less often with the improvements that have been made.
There is already a way to restore classic skin default arrangements. Similarly, modern skin windows can be returned to their default arrangements by allowing the studio.xnf file to be re-created. But then the windows need to be adjusted and moved back to where the user likes to have them. In addition, the studio.xnf file saves more than window arrangements and then this additional info needs to be recaptured over time as the skin is used.
It is easy for a point & click user to slightly move a window accidentally during a session, but not as easy to move it back where it was. Sometimes a crash causes an intentional re-arrangement to be lost. It would be good to have a way for window arrangements to be returned to the way they were at the start of a session during a session or saved before shutdown after an intentional re-arrangement. This would be especially useful during this beta testing period.
I've been trying to make backups of the winamp.ini and studio.xnf files between sessions (where most of the major window arrangement info is stored). Sometimes I restart WACUP several times a day and don't make these backups between each session. So usually when I need to use info from the backups to edit these files, it is not recent.