--- PDF\API2\Basic\PDF\Pages.old	Fri Jul  7 04:53:59 2017
+++ PDF\API2\Basic\PDF\Pages.pm	Tue Mar 26 12:24:25 2019
@@ -191,7 +191,7 @@
     {
         for ($pindex = 0; $pindex < $ppnum; $pindex++)
         { last if ($ppages->{'Kids'}{' val'}[$pindex] eq $ppage); }
-        $pindex = -1 if ($pindex == $ppnum);
+        $pindex = -1 if ($pindex == $ppnum - 1);
     }
 
     $ppages->add_page_recurse($page->realise, $pindex);
@@ -216,7 +216,7 @@
             $ppnum = scalar $ppages->{'Kids'}->realise->elementsof;
             for ($pindex = 0; $pindex < $ppnum; $pindex++)
             { last if ($ppages->{'Kids'}{' val'}[$pindex] eq $self); }
-            $pindex = -1 if ($pindex == $ppnum);
+            $pindex = -1 if ($pindex == $ppnum - 1);
             $ppages->add_page_recurse($newpages, $pindex);
         }
     }