Hi,
First of all, you can switch to Resilio Sync for Docker if your NAS supports Docker, which I did.
However, if you had all your files on the directly in ResilioSync on the actual NAS, then it is an issue to somehow get them all into the Docker version, since Resilio Sync is not running to sync them.
I hope Resilio will release an updated version soon - at least when DSM 7 is released officially.