Well that is, of course, good news – but doesn’t explain why the install failed to create the folders you needed. The only other thing that comes to mind would be something like an .htaccess rule that prevents it.
It probably means that you will need to create these manually. By default they are named (under the sp-resources folder):
forum-image-uploads
forum-media-uploads
forum-file-uploads
If we still need to create the missing table manually will you be able to do that with a sql script that you can run form phpmyadmin?