I'm using SIG 1.2 Pro and I've noticed that sometime when viewing a SIG in FF 2.0.0.6 the grid of thumbnails does not populate consistently. For instance, on a good day 4 normal rows of 3 columns will be followed by an irregular row containing only 1 column, which is then followed by normal rows. But if you start moving the scroll bar or try to reposition inside the page before the page is completely loaded you can get the ugly ugly, which is when all rows contain only a single column even though there is room for a minimum of three columns.
The reason I say CSS, or FF's handling of CSS, is because the source does not contain holes. I suspect it's related to the way FF tries to optimize rendering while parsing each line of HTML. In this case, however, SIG output produces some pretty amazingly long lines of HTML as it outputs the entire gallery, regardless of size, as a single line. My guess is if SIG were to be modified to produce shorter line lengths, like a line break after each thumbnail, the problems would correct itself.
This behavior is not exhibited by IE 7.
Any one else experience this problem?