LuxCal 4.7.7M crash when editing existing event

Hi,

I upgraded to LuxCal 4.7.7M but now I obtain crash when editing any existing event :

Warning: require(C:\Servers\sites\xxxxxx): failed to open stream: Permission denied in C:\Servers\sites\xxxxxx\index.php on line 279

Fatal error: require(): Failed opening required './' (include_path='.;C:\php\pear') in C:\Servers\sites\xxxxxx\index.php on line 279

If I create a new event and try to edit it, same error.

Please, do you have any idea ?

Thank you