I'm not sure if you're able to save layer styles in PSE6 (I know you couldn't in PSE3)...but click on another layer that has the same "low" drop shadow on it and then see if there's an ability to save it somewhere?
If not, the best thing I can think of is always having another layout open with that drop shadow in it, you can copy/paste a shadow to your layers from it (forgive me if these are slightly off, lol - Layers > Layer Styles > Copy Layer Style or Paste Layer Style). Something like that.
