I'm not a full time Indigo user so my experience will not be that helpful in this instance but I will try.
Have you set up the restful API for indigo (
http://wiki.indigodomo.com/doku.php?id= ... stful_urls )
When you know the URLs you need go to Home Remote and select "add action".
Press the "URL" button and then enter the indigodomo URL and action name.
Select "post/put" and then "name:pass". Add your username and password in the format username:password then press "add to action", then "add action".
Pull down your todsy screen and add the widget and see if the button works.