Meshing bug: misidentification of overlapping edges

[cmd8]

I believe there is a bug somewhere in the BAMG code used to identify overlapping edges (and also in the mortar construction). Below is a simple reproducer that is pretty contrived, but I have found this issue on other meshes with small clearances, especially when using adaptmesh(). I have looked into the bamg source code to find the issue, but the code and comments are difficult to understand... Does anyone with more familiarity with bamg have ideas for a fix?

real n0 = 64;
real n1 = 16;
real R = 1.0;
real L = 2*R;
real H = 2*R;
real h = 1.0e-4;

// Define borders
//  o-------4-------o
//  5               |
//  o--6--o         |
//         7        3
//  o---8---o       |
//  1               |
//  o-------2-------o
border C01(t=0, 1){x=-R; y=R*(1-t); label=1;}
border C02(t=0, 1){x=-R+L*t; y=0; label=2;}
border C03(t=0, 1){x=L-R; y=H*t; label=3;}
border C04(t=0, 1){x=L*(1-t)-R; y=H; label=4;}
border C05(t=0, 1){x=-R; y=H-(H-R-h)*t; label=5;}
border C06(t=0, 1){x=-R+(R-0.05)*t; y=R+h; label=6;}
border C07(t=0, 1){x=-0.05*(1-t); y=R+h*(1-t); label=7;}
border C08(t=0, 1){x=-R*t; y=R; label=8;}
// Assemble mesh
mesh Thg = buildmesh(C01(n0*R) + C02(n1*L) + C03(n1*H) + C04(n1*L) + C05(n1*(H-R-h)) + C06(n1*(R-0.05)) + C07(n0*sqrt(0.05^2+h^2)) + C08(n0*R));