I removed my entire gallery some years  back and as I recall...I had to do it one at a time...( I wouldn't have expected anyone from staff to go delete me entire gallery by hand  for me anyway)...

I'm not sure if they have a "Nuke Entire Gallery" command now or not...but if they don't...the best way I found was to make use of the "Right Click > Open in new window" command when clicking on the Delete button... It'll save you from having to navigate all the way back to your gallery after every image...As I recall..I had mine deleted in about 20 to 30 minutes.

 

Tom

“The fact that no one understands you…Doesn’t make you an artist.”