Error on Access to Forms

Hi,
I get a persistent error while trying to view the "Access to Forms" window in the Access Rights section.
After a while a pop-up tells me that a technical error occured probably due to a bad connection and offers me to contact my administrator.
I can access every other windows just fine.
I'm running ProjeQtOr v6.2.5 with Apache/2.4.27 (Debian) / PHP Version 5.6.30-0+deb8u1 / mysql Ver 14.14 Distrib 5.6.30
In the log file I cut and paste what appears when I'm trying to access that window :
2017-08-02 18:05:59.145 ..... SCRIPT .... 192.168.0.10 /projeqtor/view/parameter.php
2017-08-02 18:05:59.170 ..... SCRIPT .... 192.168.0.10 Page=parameter.php
2017-08-02 18:05:59.177 ..... SCRIPT .... 192.168.0.10 getProfile(objectOrIdProject=Audit #61)
2017-08-02 18:05:59.268 ..... SCRIPT .... 192.168.0.10 ->/view/parameter.php
2017-08-02 18:06:13.068 ..... SCRIPT .... 192.168.0.10 Page=checkAlertToDisplay.php
2017-08-02 18:06:13.075 ..... SCRIPT .... 192.168.0.10 getProfile(objectOrIdProject=Audit #61)
2017-08-02 18:06:13.176 ..... SCRIPT .... 192.168.0.10 /projeqtor/view/parameter.php
2017-08-02 18:06:13.200 ..... SCRIPT .... 192.168.0.10 Page=parameter.php
2017-08-02 18:06:13.208 ..... SCRIPT .... 192.168.0.10 getProfile(objectOrIdProject=Audit #61)
2017-08-02 18:06:13.220 ..... SCRIPT .... 192.168.0.10 ->/view/parameter.php
2017-08-02 18:06:27.015 ..... SCRIPT .... 192.168.0.10 /projeqtor/view/parameter.php
2017-08-02 18:06:27.037 ..... SCRIPT .... 192.168.0.10 Page=parameter.php
2017-08-02 18:06:27.042 ..... SCRIPT .... 192.168.0.10 getProfile(objectOrIdProject=Audit #61)
2017-08-02 18:06:27.122 ..... SCRIPT .... 192.168.0.10 ->/view/parameter.php
2017-08-02 18:06:40.931 ..... SCRIPT .... 192.168.0.10 /projeqtor/view/parameter.php
2017-08-02 18:06:40.956 ..... SCRIPT .... 192.168.0.10 Page=parameter.php
2017-08-02 18:06:40.964 ..... SCRIPT .... 192.168.0.10 getProfile(objectOrIdProject=Audit #61)
2017-08-02 18:06:41.089 ..... SCRIPT .... 192.168.0.10 ->/view/parameter.php

Any idea what's happening here ?
Thank you.
Rudu