I know, stupid question but the default always seems to be by capture time and I often rearrange and rename slides.
I have searched the menus but how do I get the slideshow to sort by filename, not capture date?
In Library mode, either viewing a Folder or Collection, press T to Hide/Show the Toolbar. (Or View menu, Show Toolbar -- top item on the list.) With the Toolbar visable, see Sort Order. If you don't see it, click the little down-arrow on the right side of the Toolbar and select Sorting.