all right-
first - which version are you using?
About the thumbs - you can display the thumbs in the thumbnail strip smaller than on the thumbstrip - if this is the case they appear bigger once because the cache image is not gerneted yet and I cannot read the real size - once this is done they all appear in the real size.
2nd - do you want the thumbs to be clipped images or real ones?
in your case I think:
$resize_only_if too big - does not matter
$use_small_pic_size_as_height=true - then all images have the same heigt - the thumbnail strip does not jump!
your setting seems like a normal one like I use in many of my demos - and 36 is not a problem wih the images
- 30 000 would be
.
Michael