[Wannier] Initial choice for projection

[seunghwan lee]

Dear All,

I went through (5,5) nanotube example (with no problem) and I have been
playing with other parameter choices to learn more about wannier90.
One of the things that I tried was using different initial projection. 
For example, I tried

Begin Projections
Random
C:pz:x=0,0,1
End Projections

It went through without a problem although the final results (band 
structure, DOS) were somewhat different from the example.

HOWEVER, when I used the same random projection with 4 unit cells
(80 carbons, num_bands = 320,num_wann  = 200) it didn't work and I got the 
following message.

 The trial orbitals for disentanglement are not orthonormal
 Exiting.......
 Error in dis_main: orthonormal error 1

I even tried the same projection like the one in example for 4 unit cells,
but it didn't work neither with the same error message.

My questions are:

[1] Is there an option to orthogonalize the trial orbitals?
[2] Why the random projection works for 1 unit cell, but not for 4 unit
 cells?
[3] What is the best option for initial projection in carbon nanotube 
 system?

Thanks in advance,

Regards,

Seunghwan Lee
University of North Carolina