I too had to do the “a2enmod headers” and stumbled on the “http://os_addr/su ” typo. Sorry that I forgot to mention that!
Another small change with apache is that the web files now need to go into /var/www/html rather than just /var/www.
I added everything to /var/www not /var/www/html and it worked fine.
But, I did not use the <Directory> </Directory> tags. I assumed that when you specify a directory to “limit the scope” of the commands, the commands would apply to all child subdirectories of the specified directory also. So, adding <Directory /var/www/> wouldn’t narrow the scope at all, so might as well leave it out.
I think that if I added additional .js or .html files for something unrelated to OpenSprinkler then it would be better to have the OpenSprinkler stuff down in in its own directory. Then I could use the <Directory> tag to make the commands specific to OpenSprinkler.