How do I correctly (import (srfi :42)) in Chez scheme?

Question

(System: centos 7, 64 bits)

I am attempting to import srfi-42 into my program. This is the first srfi in Chez Scheme for me.

The srfi lib is at:

/home/cecilm/play/ChezScheme/chez-srfi/srfi

I added this dir to my .emacs :

(setenv "CHEZSCHEMELIBDIRS"
    (concat
      "."    ":"
      (getenv "$HOME") /play/ChezScheme/chez-srfi" ":"
      (getenv "PATH")))

In emacs, geiser starts chez. emacs seems to know about this dir:

> (library-directories)
(("/home/cecilm/play/ChezScheme/chez-srfi"
   .
   "/home/cecilm/play/ChezScheme/chez-srfi"))

The repl seems to import srfi-42:

> (import (srfi :42))
> (list-ec (: i 5) (* i i))

Exception: attempt to reference out-of-context identifier error

I thought "i" was a problem, so I defined "i" in a let:

> (let ((i 0)) (list-ec (: i 5) (* i i)))

Exception: attempt to reference out-of-context identifier error

What do I need to do to actually use an import? This is the first time I have used any imports in Chez Scheme.

Does "list-ec" need a qualifier?

I obtained the srfi's from git Is this a "standard"? Is there a more "official" repo for Chez scheme?