A huge problem w/ LiveCycle Designer is (this is what I found), by clicking the "Submit via Email" button, the Adobe Reader is trying to connect to the local default email program, like outlook express.
However, public computers are usually banned the users to launch an email program, and users are more likely to check email within a webpage. I noticed a number of students close the Reader after filling out the form but failing to send back the data.
Anyway that I can allow a Reader user to be able to save .xml data file so he/she can attach to web-based email?
If you have Acrobat there is a subset of Reader Extensions functionality available in there that will allow you to Reader Extend the form to do local saves. The license agreement limits you to 500 uses. If you need more than that there is a server option that is more expensive but has no limits on users.