I'm tying to get my domain mapping works since 2 days now and open a ticket because not any tip found in the forums and doc have solved the problem.
I followed your step by step install guide and have created a new site under /wpplugin/ for the domain name plugin-wordpress.info.
When I'm going into Tools/Domain Mapping in this website admin and enter plugin-wordpress.info and any of the dropdown options and try to browse the website I am redirected to the main domain (grayworld.fr).
When I check the wpmu_domain_mapping table nothing is added.
I tryed to manually add the domain info in that table and was able to browse plugin-wordpress.info but get the following error message into the superadmin all sites page (I think the not only this table is updated):
Parse error: syntax error, unexpected T_STATIC in /home/grayworl/www/WpMu/wp-content/plugins/domain-mapping/classes/Vendor/Punycode.php on line 75
I have now removed this entry but because I was able to browse the mapped domain before that, I assume that's not a dns issue. Also I was able yesterday to map a domain but not anymore. I tried then to install again the whole without anymore result.
I can email you any access you need to help me because I wasn't thinking the install were a nightmare and a big wast of time.
Thanks for you support,