Hello,
Thank you for the plugin.
I just would like to suggest adding the possibility to write the default values in custom parameters in MULTILINE please (currently it only works in one line).
I believe it’s a very easy fix: just add a ‘s’ at the end of the regex on the line 208 in preg_match_all function from shortcoder.php: 
I tested and it works great for me.
However, when you’ll release an update, it’ll be overridden since there’s no hook that encloses that part of the code… That’s why it would be great if you could add this in the next update please.
Thank you!
Rolm