==== Calendar ====

To have the calendar with the first day of week configurable (I prefer monday as the first day of week), add/change the following in actions/calendar.php:

Add to the contants section:
%%(php)
#+first DOW configurable
define("FIRST_DOW", "Monday"); # set this to "Monday" or "Sunday"
#-first DOW configurable%%

Right after the definition of ##$firstwday## (##$firstwday = strftime('%w',strtotime($datemonthfirst));## add the following lines:
%%(php)
#+first DOW configurable
if (strtolower(FIRST_DOW) == "monday") {
$firstwday -= 1;
if ($firstwday < 0) {
$firstwday = 6;
}
}
#-first DOW configurable%%

And replace the definition of ##$tmpTime## (##$tmpTime = strtotime("this Sunday");##) with:
%%(php)
#+first DOW configurable
//$tmpTime = strtotime("this Sunday"); # get a starting date that is a Sunday
$tmpTime = strtotime("this ". FIRST_DOW); # get a starting date that is a Monday or Sunday
#-first DOW configurable%%

Thats it.