Just downloaded Amiblitz 3.6.1 on Sourceforge. Didn't know it was open source now, shows how out of touch I am with programming languages.
I just read in a forum post that it's AGA only and requires a FPU to run, whereas Blitz 2 didn't.
Not a problem as my A1200 has a FPU, and there is always WinUAE.
I will give all this a look through and dig up some tips and help resources to read.