Recently machine translation faced issue related to out of the box token expiry. Customer needs to update token configured in cloud config for translation. 

Please attach full error stack trace. Also what path you're pasting for XCI file?

Steps are same for both cloud service and on-prem. Also sharing docs for on-prem configurationhttps://experienceleague.adobe.com/en/docs/experience-manager-65/content/forms/adaptive-forms-advanced-authoring/generate-document-of-record-for-non-xfa-based-adaptive-forms#use-a-custom-xci-file

Please share snap of cq:template node and resource of proxy component. 

Please use following documentation to provide custom xci in AEM forms https://experienceleague.adobe.com/en/docs/experience-manager-cloud-service/content/forms/adaptive-forms-authoring/authoring-adaptive-forms-foundation-components/generate-document-of-record-for-non-xfa-based-adaptive-forms#use-a-c...

Are you using core component based forms? Also on which version are you on? I can see the options with data value and display text on my local.