According to my knowledge Synology NAS is used for storage there is no windows installed on it, The middle ware contains JRDC2 service + Microsoft SQL Database so i don't think it would work on a Synology NAS
Yes you can just redirect the JRDC2 service to what ever database you would like, once we send the source codes we will also send the SQL Database SQL Script which you can import it to any database you would like