FCG is acting very weird.... not showing

[labecs]

After hours of trial an error I was able to fix the fact that FCG stopped working every few minutes.
I was being able to see the FCG working fine, and 5 minutes later I just got the blank gallery.
I finally managed for it to stay put for a while (keeping fingers crossed), however, I cannot see it in Safari, IE, and I can see it in Firefox in one computer, but not in another, no matter how many times I refresh, clear cache and everything you can imagine. I tested it in the default theme, and the same thing happens. I see it in FF, not in Safari and IE and the other FF computer.
I have deleted the plugin, downloaded it again, installed it again. Same problem. It also only works when I put it in Category, I can't get it to work with post id's.
I am working on a virgin site with only one other plugin, Reveal ID's, but even when I disable it, no change. I was also using Lifestyle 3.0, so I switched to 4.0, but no change.
I am at the end of my rope! Please somebody tell me what to do! I have FCG in 6 other sites and it works fine in them in every browser, but not this one, eventhough it's the same theme as the others.
I tried installing other slideshow plugins but some I find too complicated, and I can't get Featured Story to show at all, which is a simpler one.

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