On the SmartFTP issue...FTP is just not reliable...I don't think it's a TCH issue either. I just think FTP can be hit or miss.
A more reliable approach, I think, when it comes to uploading something like MediaWiki is to download the tar.gz file from MediaWiki, upload that file to your public_html directory using the CPanel File Manager, and then extracting the files using that File Manager. This way, you only have to upload one file, and CPanel handles the decompression.