No data lose will occur.

It is a cache folder needed to speed up image previews. 

I am confused, what would happen to the data base if I delete the  PreResampled folder. Will I lose the "Library" or the "Yellow Box" that the image has been downloaded? Or the search feature? Will it show an "X" and not locate the file. I am losing space on my Local Disk drive but do not want to delete if it was cause others issues listed above? 

Yes, it is safe to delete it.

It will be recreated when needed but you can keep deleting it, periodically.

I would like to delete the images in the PreResampled Folder. Is that safe?

thanks