The most important thing to know when migrating from BAM 11g to 12c is to check the box "Turn this query into a continuous query" for any any charts that you want changing dynamically in real-time. This check-box can be found in the "Runtime-Interaction" section under "Active Data". This is NOT available for all chart types. See the Using Active Data section of the documentation for specific details.
Using BAM 12c with an 11g Database
Prior to installing BAM 12c, Oracle recommends that you set-up your database to use SecureFiles. SecureFiles is the default storage mechanism for LOBs starting with Oracle Database 12c and Oracle strongly recommends SecureFiles for storing and managing LOBs, rather then BasicFiles. BasicFiles will be deprecated in a future release. They will need to set a parameter to make SecureFiles the default before installing the SOA tables.