I just did a post on my blog about the Nivo Slider. It's at
http://usingflux.blogspot.com/2012/05/image-gallery-with-nivo-slider.html
Your question is a good one - I forgot to include this in my blog
post :
When you first insert the Nivo Slider widget, it creates a div called
"slider" with three IMG tags with three example images. When you are
in edit mode, you can see these images stacked on top of each other.
If you don't want to see an image when in edit mode, you can set the
'display' attribute to 'none' for that IMG tag. To do this, select
the IMG tag - best to do this in the Navigator - then bring up the
Inspector, find the 'display' attribute (I think it's under 'misc' -
I'm not at my computer right now). Once you find 'display', set it
to 'none', and that image will disappaer during editing. It will
display when the gallery is operating. If you want to show the image
again when editing, simply set 'display' to 'block' or remove the
attribute entirely.
jvcbiggles