For an older, heavily modified ajax-dashboard.php, the key things to modify are likely:
1) replace all
${variablename}
with
{$variablename}
2) replace all
split(...)
with
explode(...)
3) there are multiple variables that had null string instead of null arrays. Check the error message and change
$variable ='';
to
$variable = array();
for those variables so used, change
if($variable == '')
to
if(!isset($variable[0])
4) some variables weren't initialized with a value before being used.. insert
$variable = '';
for strings and
$variable = array();
for arrays.
But.. Vasco has the best advice.. start with the current 6.95h version and do your mods there. Be sure to replace the four other PHP support scripts in the .zip too -- they all work with PHP 8+.
Good luck.