File locations for saving smart object .psb files

Zeno, I really appreciate your help in trying to solve this problem for me.  But I do not think that you have much experience using smart objects.  I think that I really need someone to help who is experienced in using smart object layers.

To clarify some more....

I have a .psd file with layers that is stored on my data drive.  I convert a layer to a smart object so that I can preserve its resolution.  I open this layer by double clicking on it.  It comes up in a new window and I can make adjustments to it in Photoshop like any other image/.psd file.  When I close it, it takes a long time to save and I have a lot of disk activity on my OS drive.  I believe what is happening is that it is using that \temp\ directory as some sort of scratch device that it deletes on its own later.  But I am not sure of this.  If I close the file, it asks if I want to save, takes a long time, then goes back to the main .psd file with the changes to my layer.  Instead of simply closing the file, if I do a save as to another location, Photoshop saves the file as a .psb file but the main .psd file does NOT get updated with the changes.  So clearly, "save as" is not the answer.

I just want to make Photoshop use my scratch/data disk to save any temporary .psb smart object files.  Maybe it is not possible.  But I need someone who has more experience than me to weigh in if this is going to get solved one way or the other.