"I am beginning to think that Devel::Cover is not an option for perl 5.18.1"

I'm running 5.18.1 — I've just successfully installed Devel::Cover 1.09:

$ cpan

cpan shell -- CPAN exploration and modules installation (v2.00)
Enter 'h' for help.

cpan[1]> install PJCJ/Devel-Cover-1.09.tar.gz
...
  PJCJ/Devel-Cover-1.09.tar.gz
  /usr/bin/make install  -- OK

cpan[2]>
[download]

And then, because I didn't want an old version, I successfully installed the current version:

cpan[2]> install Devel::Cover
...
  PJCJ/Devel-Cover-1.12.tar.gz
  /usr/bin/make install  -- OK

cpan[3]>
[download]