Include email attachment in new content Rule
If anyone else is struggling with this problem (and, I did find quite a few that were), I've found a work around.  First, it appears like this may be a known bug.  Given that, I found the work around at #25 worked for me.  In my case, I had to tweak the attachments value in the rule to look like this...

[node:field-file-attachments:file:path]


Note: no preceding path was required.  With the above, I now get attachments in emails that are generated via a rule.