The HTTPS errors are due to a missing certificate in the chain that's being presented.  
  
  
openssl s_client -connect breeding.zone:443 
  
 0 s:/OU=Domain Control Validated/OU=COMODO SSL Unified Communications/CN=www.studio3x.com
   i:/C=GB/ST=Greater Manchester/L=Salford/O=COMODO CA Limited/CN=COMODO RSA Domain Validation Secure Server CA
 1 s:/C=GB/ST=Greater Manchester/L=Salford/O=COMODO CA Limited/CN=COMODO SSL CA
   i:/C=SE/O=AddTrust AB/OU=AddTrust External TTP Network/CN=AddTrust External CA Root
 2 s:/C=SE/O=AddTrust AB/OU=AddTrust External TTP Network/CN=AddTrust External CA Root
   i:/C=SE/O=AddTrust AB/OU=AddTrust External TTP Network/CN=AddTrust External CA Root
 
So certificate 0 is issued by COMODO RSA Domain Validation Secure Server CA but the next certificate presented in the chain is COMODO SSL CA, which I don't think is in the path for the cert at all. Presumably our desktops have the intermediate certificates in their stores, so still work..
 
You want (certs from https://support.comodo.com/index.php?/Default/Knowledgebase/Article/View/979/108/domain-validation-sha-2
 
<your cert>
COMODORSADomainValidationSecureServerCA
COMODORSAAddTrustCA.crt
 
Which terminates in the browser supplied UserTrust CA