The page at https://www.cpcwiki.eu/index.php/Special:UploadWizard pretended to work when I tried to upload three PNG screenshots, showing the thumbails for each on screen, saying "Uploaded" and "All uploads were successful!", but the files didn't appear on https://www.cpcwiki.eu/index.php/Special:NewFiles.
Uploading the same files individually via the standard https://www.cpcwiki.eu/index.php/Special:Upload page worked fine.
Yeah, the multi upload also never worked for me.