In the past few years, I've managed to get the last source code release to compile on Amiga OS 3.x using SAS/C. This version is still not /exactly/ as Blue Ribbon left it; Alfred Faust made some adjustments to header files.
Alfred Faust has refused to release the source code to all of his later improved versions and is now in poor health.
B&P made use of InovaTools for its GUI; I have these software packages also.
I'm afraid that anyone picking up the B&P source code for modernization is going to have to deal with many of the same issues that Alfred already dealt with in his later versions, without having the code to Alfred's improvements. He made a lot of changes w/r/t RTG and chip mem usage, IIRC. He also changed the timing system of B&P, I think, which may have resulted in better timing.