Error included below, seems its missing this file, i even checked the rc2 package and did not see it.

[Icy Phoenix Debug] PHP Notice: in file /viewtopic.php on line 1857: include_once(./mg/includes/functions_feedbacks.php) [function.include-once]: failed to open stream: No such file or directory

[Icy Phoenix Debug] PHP Notice: in file /viewtopic.php on line 1857: include_once()

[function.include]: Failed opening './mg/includes/functions_feedbacks.php' for inclusion (include_path='.:/usr/lib/php:/usr/local/lib/php')

[Icy Phoenix Debug] PHP Notice: in file /viewtopic.php on line 1858: include_once(./mg/common.php) [function.include-once]: failed to open stream: No such file or directory

[Icy Phoenix Debug] PHP Notice: in file /viewtopic.php on line 1858: include_once() [function.include]: Failed opening './mg/common.php' for inclusion (include_path='.:/usr/lib/php:/usr/local/lib/php')

[Icy Phoenix Debug] PHP Notice: in file /viewtopic.php on line 1859: include_once(./mg/language/lang_english/lang_mg.php) [function.include-once]: failed to open stream: No such file or directory

[Icy Phoenix Debug] PHP Notice: in file /viewtopic.php on line 1859: include_once() [function.include]: Failed opening './mg/language/lang_english/lang_mg.php' for inclusion (include_path='.:/usr/lib/php:/usr/local/lib/php')

[Icy Phoenix Debug] PHP Notice: in file /viewtopic.php on line 1860: include_once(./mg/language/lang_english/lang_feedbacks.php) [function.include-once]: failed to open stream: No such file or directory

[Icy Phoenix Debug] PHP Notice: in file /viewtopic.php on line 1860: include_once() [function.include]: Failed opening './mg/language/lang_english/lang_feedbacks.php' for inclusion (include_path='.:/usr/lib/php:/usr/local/lib/php')

Did you read the comment in constants.php?

This feature is not available for standard Icy Phoenix.

I have been committed to create it and it is available only as an extra customization.