Dear Bastien,

The error

> Wrong type argument: listp, t

was due to the following line

(add-hook 'org-mode-hook 'predictive-mode)

which was there in the .emacs file.

While predictive mode is on [without (add-hook 'org-mode-hook
'predictive-mode) in .emacs] in org-mode buffer, C-c C-e p produces an
empty folder .predictive, in the folder where .org file is located. If I
use (add-hook 'org-mode-hook 'predictive-mode) in .emacs then the generated
.predictive folder contains all the .el and .elc files.

Thanks.
-----------------------------
Sanjib Sikder