Spank bank saves are generate when you play, they're actual savegames (so they keep stuff like custom names).Old saves doesn't unlock scenes in the spankbank?
You can take this existing spankbank and dump it into your save-folder if you want.
Savegame Paths:
Windows: %USERPROFILE%/AppData/LocalLow/FlexibleMedia/Paradise Lust
OSX: ~/Library/Application Support/FlexibleMedia/Paradise Lust
Linux: $XDG_CONFIG_HOME/unity3d/FlexibleMedia/Paradise Lust