Hi,

The message you receive ("Band in a Box is not optimized for your MAC and needs to be updated") is a generic message that is displayed the first time a 32 bit app is started on OSX (since the machine was last restarted). This message started to occur in april 2018 on OSX 10.13 (High Sierra). It is only an informational message, informing you that the app is 32bit and that OSX will drop support for 32bit apps soon (most likely in next version).

Hence it should currently not prevent BIAB from working correctly (even though it will most likely do after the next OSX update). I run BIAB successfully on multiple macs, one of them running 10.14.4.

Hence what you experience is (to my understanding) not related that information message. I would suggest you contact PG Music support, they can usually resolve most issues quickly.

I hope you have that problem solved!

Best regards
/Björn