I'm making some test with domain mapping but without success for the moment.
I've tried with another plugin before, redirecting through de ANAME and now I've tried with your own plugin redirecting through A with a dedicated IP (18.104.22.168), but the result is the same, it goes to a blank page as you can see here: http://www.kwante.com/.
What I've done:
1 - I asked for a dedicated IP for the domain zlime.net to my host (which is 22.214.171.124),
2 - I've added to wp-config.php the: define( 'SUNRISE', 'on' );,
3 - I've moved sunrise.php to the wp-content folder,
4 - I've entered in the domain mapping of the subdomain http://happycasa.zlime.net/ (a test sub domain) the following:
-> custom domain: http//kwante.com (it doesn't show the www)
-> Original Blog Address: http://happycasa.zlime.net/
5 - on my domain name kwante.com I added a redirrection by IP to 126.96.36.199
6- I've waited a couple of hours.
So I'm pretty sure I did something wrong but I can't see what...
Could you please help me ?