<<MBv1.2.m;

<<AMBRE.m;

<<MBnum.m

m=0;

invariants = {p1^2 -> m^2, p2^2 -> m^2, p3^2 -> m^2, p4^2 -> m^2, 
    p1*p2 -> 1/2*s - m^2, p3*p4 -> 1/2 s - m^2, p1*p3 -> 1/2*t - m^2, 
    p2*p4 -> 1/2*t - m^2, p2*p3 -> 1/2*u - m^2, 
    p1*p4 -> 1/2*u - m^2} /. u -> 4 m^2 - s - t;

repr = MBrepr[{1}, {PR[k1, m, n1] PR[k1 + p1, 0, n2] PR[k1 + p1 + p2,m, n3] PR[k1 - k2, 0, n4] PR[k2, m, n5] PR[k2 + p1 + p2, m, n6] PR[k2 + p1 + p2 + p4, 0, n7]}, {k2, k1}];

SetOptions[MBnum, Analytical -> True, Numerical -> False, ShowMBrep -> True];

MBanalytic=MBnum[repr, 0, {s -> -5, t -> -7}, {n1 -> 1, n2 -> 1, n3 -> 1, n4 -> 1, n5 -> 1, n6 -> 1, n7 -> 1, n8 -> 1}, 2] // AbsoluteTiming

MBintegrate[MBanalytic[[2]],{s -> -5, t -> -7}] // AbsoluteTiming

