It seems to be the result of reading a .w file as .curv, i.e., garbage.
With the files you shared I "get" the error but with "2 vertices":
***************************************************************************
** Error: The number of vertices in the surface (163842) and the source map (2) do not match.
***************************************************************************
In the good news: FreeSurfer .w files are now supported in Brainstorm:
When using Import texture, select both the lh and rh file
