The size for sliders is 1170x500px
Shrink them to 72dpi if they’re higher.
Solution for that has been posted here.
I’ve provided the solution in this thread mentioned above.
Hope this helps.
Get this plugin.
It lets you create a page that’s redirecting to your chosen address.
Then when you have your special page ready, link the slide button to this page, it will take visitor directly to the target address.
Voila!
