Problem phpthumb in flexicontent category and fleximodule

Hello, lde back with a new concern on the old version of my site the problem was already there, I used to FLEXIcontent modules or menus to categories the option to extract the main image of the article.
And every time I avias this erreure regularly on my homepage or my categories:
"phpThumb() v1.7.11-201108081537 phpthumb.sourceforge.net Error messages disabled"

Working on my new version I try to delete this erreure, so I tried to use the image fields FLEXIcontent but it does not solve the problem.
I also modify the file components /com_flexicontent/ libraries/phpThumb/phpthumb.class.php explained here.

Still nothing as you can see on this screenshot the problem is still present?
I use a latest version of flexicontent and joomla 2.5

Inside components/com_flexicontent/libraries/phpthumb/phpthumb.class.php
find:
var $config_disable_debug = true;
and set it to false:
var $config_disable_debug = false;

clean cache and revisit the page, the actually error message should appear, and the post back here

I have made ​​this change as explained in the post but the problem persists.
My website www.gamerlive.fr/ is online and open but it's pretty annoying nonetheless.

you have made the changed and you did not get the error message to print?

I have modified the file as explained but I still get the error that appears randomly on a mignature FLEXIcontent module or a mignature a menu category. Just updated the page for the changes was an error module.
You can see it on my homepage: www.gamerlive.fr

Is it possible that this is due to a possible right chmod on a file ftp?

Ok , the setting to print was in a different place:

Inside components/com_flexicontent/libraries/phpthumb/phpthumb.class.php
the:
$PHPTHUMB_CONFIG = true;
should become:
$PHPTHUMB_CONFIG = false;

I have enabled it on your site, it is strange, the error message printed say that usage is incorrect, and it is random

I see that the error appears in both your live site and in the development site. When did the problem start?

I have opened a URL of single thumbnail and on out of 10-15 times (clicking refresh) it gives this error