Official comment
You can sync unlimited files in Syncplicity, but as a practical matter you would find the experience far better if the data were in folders with far less than 30k items in an individual folder. If there is a high rate of change among the files in a folder with 30k of them, things are likely to become unsynced. It can work if the use case is largely archival and the files aren't changing frequently.
Integration with Office 365 is something we are considering for a future release, it is not available currently. You can provision users using AD sync with Syncplicity partners Okta, OneLogin, or Ping Identity. Details of this are covered here: https://syncplicity.zendesk.com/hc/en-us/articles/202392754