shortcode buttons + downloads

[gvdsleen]

Hi, am using shortcodes to create a button. Want to direct to a bought pdf file by non-members.

Option 1:
button for paid access?
[button url="http://www.mydomain.org/?s2member_file_download=docname.pdf&s2member_file_download_key=< ?php echo s2member_file_download_key("docname.pdf"); ?>" target="_blank" color="green" ]start download now![/button]

Is NOT working. However, next example is:

Option 3:
<a href="http://www.mydomain.org/?s2member_file_download=docname.pdf&s2member_file_download_key=<?php echo s2member_file_download_key("docname.pdf"); ?>">Link for paid access:</a>