Since release of bulk upload I was getting same bug report over and over again. Finally working with forum members realized that some Linux servers were using case sensitive file names I guess it was affecting 10%-20% of all installations. Finally it is fixed in Wallpaper Script version 1.2.3 which can be downloaded from script page. Thank you all forum users for pointing this and helping to fix.
Other big bug fix is UTF-8 category names and URL. Especially for Russian characters it was generating wrong category links which were resulting as 404 pages.
Also fixed category editing bug where instead of renaming category it was adding new one.
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