I deleted the certificate and I tried to recreate the request and reimport the certificate adding your intermediate cert as you did.
/certificate> import file-name=uala_datalit_intermediate.crt
/certificate> import file-name=certificate-request_key.pem
Then I selected the certificata in services and in hotspot, but now I get
maybe I should buy a certificate from a provider indicated in the wiki such as rapidssl, godaddy, register, opensrs, thawte, but they are more expensive and there are lot of possibilities, which one should I buy?