Had an issue too that i could not fix, resulting in just a blank page.
Deleted all files, re-installed mediawiki, re-imported product and i was on-line again.
Looks like this now:
http://www.fortforum.se/medwiki/inde...itle=Huvudsida
Never understood what the problem was unfortunately, but my guess is that it was a conflict somewhere, as the script do not uninstall the product.