FileMaker 15 was released today by FileMaker Inc.
Our MBS Plugin supports FileMaker 15 for a few months already.
Version 6.0 was updated to support FileMaker 15 by using the latest Plugin SDK.
The upcoming release 6.2 will include a few little bug fixes we will find now when testing with final FileMaker 15 version.
So please update to version 6.x if you haven't already.