Thanks Eduan! This is nearly what I need.
The only thing is that this plugin does not upload pictures the same way WordPress image uploader does it, meaning it does not offer to embed a smaller down-scaled version of the image linking to the full sized image, it does not offer to write in the image tags right there before inserting. It only uploads the file to s2member-files and then links to it with the filename of the uploaded file.
It ads something like this to the HTML/Visual viewer:
<a href="http://mydomain.com/?s2member_file_download=MyPhoto.jpg">MyPhoto.jpg</a>
When I would like it to add something like this:
<a href="http://mydomain.com/?s2member_file_download=MyPhoto.jpg&s2member_skip_confirmation"><img src="http://mydomain.com/?s2member_file_download=MyPhoto-200.jpg" title="Sowill" width="200" height="149" /></a>
it using the WordPress image rescaling engine to generate that smaller resolution thumbnail that links to the full image.
For now, if I choose to use s2member, which I probably will, I tried memberwing-x which didn’t look right for me and I only looked at http://www.tipsandtricks-hq.com/wordpress-emember-easy-to-use-wordpress-membership-plugin-1706 as a potential other choice, but I guess s2member looks to be great for now.
I think I’ll look for a macro one-click plugin so that I can add all my usual code in a one click process, then have my FTP client open and drag and drop the full size image and generate the thumbnail using http://www.rw-designer.com/picture-resize then just edit the titles in the standard embed code.
I think my standard embed code is going to look something like this every time at the bottom of my partially restricted posts:
[s2If !is_user_logged_in()]
<table>
<tbody>
<tr>
<td><a href="http://mydomain.com/wp-login.php">Logged-in</a> Members ($XX/year) <a href="http://mydomain.com/become-a-member/">Join now!</a> can see a picture here. <a href="http://mydomain.com/become-a-member/">why become a Member</a></td>
</tr>
</tbody>
</table>
[/s2If]
[s2If is_user_logged_in()]
<a href="http://mydomain.com/?s2member_file_download=MyPhoto.JPG&s2member_skip_confirmation"><img src="http://mydomain.com/?s2member_file_download=MyPhoto-200.jpg" title="For Members only, click for full size" width="200" height="149" /></a>
[/s2If]