I did not realize there was activity in this brewtroller repository.
I tried three version of the Arduino environment and had errors in two of them.
The old BrewTroller_arduino-1.0.5-r2_Build_1 does compile BT 2.7.12 with many warnings.
I tried Arduino 1.6.6 with the third party board addin and it looks like it compiles the modules but fails on a avr-g++ invocation with a -MMD switch.
When I tried Arduino 1.8.5 it failed on the first compile.
Is there a known good version of the Arduino environment can compile BT 2.7.12?
Thanks.