There seems to be an issue on my side too.

I launched an ec2 instance based on the suse-sles-12-sp2-v20161104-hvm-ssd-x86_64 (ami-e4a30084) and the SLES12 repositories are unavailable due to cloudregister failures.

Code:
ip-172-30-2-41:/var/log # cat cloudregister 
2017-05-23 08:41:43,809 INFO:Using API: regionInfo
2017-05-23 08:41:43,809 INFO:Using region server: 50.17.208.31
2017-05-23 08:41:43,813 INFO:Starting new HTTPS connection (1): 50.17.208.31
2017-05-23 08:41:58,828 ERROR:No response from: 50.17.208.31
2017-05-23 08:41:58,829 INFO:Using region server: 54.253.118.149
2017-05-23 08:41:58,830 INFO:Starting new HTTPS connection (1): 54.253.118.149
2017-05-23 08:41:59,486 INFO:Starting new HTTP connection (1): 54.245.112.93
2017-05-23 08:44:44,492 INFO:[Service] No SMT server found, nothing to do
2017-05-23 08:49:52,118 INFO:[Service] No SMT server found, nothing to do
Attempting to re-run
Code:
registercloudguest --force-new
just hangs with similar errors under /var/log/cloudregister.

Are the region servers having issues?