This is the documentation for ConfiForms Server/Data Center app
However, this might also work for ConfiForms cloud and in most cases it does. But please see this page to understand the differences between server and cloud versions of the ConfiForms app.
Since ConfiForms app version 2.0 we publish release notes here
Data migration is done for your automatically when you access the form for the first time. This could take some time for the first load, depending your your dataset size
There are methods to help you to understand how you data looks like and force the migration via migration APIs if you want to do so (accessible only to Confluence system administrators)
Storage analysis
[YOUR_CONFLUENCE_SERVER_URL]/ajax/confiforms/rest/storage-analysis?spaceKey=
Auto-migration
[YOUR_CONFLUENCE_SERVER_URL]/ajax/confiforms/rest/auto-migration?spaceKey=
Your tables will look different and use the cleaner styles as provided by AUI - https://docs.atlassian.com/aui/7.8.0/docs/tables.html
Your forms look cleaner as well, and also follow the guidelines and styles from AUI