Ever since after the move, it's now possible to upload attachments to posts again. I also fiddled a bit with the settings yesterday, making it possible to upload a wider selection of filetypes. Allowed filetypes include .rar and .zip, as well as other compressed extensions, image and document files and of course the most common files associated with IE modding (.are, .baf, .bam, .bcs, .d, .dlg, .itm and .tp2).
For safety reasons, files with the extension .exe is currently not permitted.
If you are unable to upload a certain file because the filetype isn't listed as allowed, drop me a PM and I'll see what I can do to to permit it for you.

Regards,
Sebastian