Setting "Page preload number" seems to have no effect:fixed:

[Aleph0]

The default is zero, and even if you change it page preloading doesn't happen. If you reload the page with F5, the setting is reverted to zero.
Only workaround is preloading the whole chapter in advanced features.

 

[Aleph0]

As of now it looks like it's working... odd ?

 

[Kisato]

Seems Holo just pushed an update.