A few things to try to hopefully resolve the 0 Upload Error:
1) Reset permalinks to 'post name' under settings >> permalinks
2) On your server, the php.ini file associated with your site, confirm that PHP Safe Mode is turned off. While you're in the file, also make sure you have 256MB (or at least 128MB) memory_allowed. If you're unfamiliar with editing php.ini files, the easiest way to confirm this would be to have your server host tech support check this for you.
3) If either of the above still does not remove the error, it may be a server HTTP Error. HTTP errors are almost always resolved by doing one of two things, though they are tricky to diagnose/resolve due to the root cause being an issue between how the server & your computer communicate. There really isn't anything we can do through our plugin to resolve this. Give these possible solutions a try and let me know how they work for you:
- resize your images before uploading (or importing) to no larger than 960px on the longest side, let me know if that helps. If not, try:
- Uninstalling flash from your computer, and reinstalling fresh from: get.adobe.com/flashplayer/? , after reinstalling, reboot your computer and reload your site.
Let me know if either of those two actions work. If not, you may need to contact your server host to take a closer look at what may be happening from their end.