Consider replacing FG_div by QuoInt

[Max Horn]

In lib/enumerators.gi this function is defined:

InstallGlobalFunction( FG_div,
    function(a, b)
        return (a - (a mod b)) / b;
    end );

For positive inputs, this is equivalent to the GAP kernel function QuoInt, so you may want to use that instead, as it's faster. In fact, perhaps change code like this:

     i := FG_div(a, y);    
     j := a mod y;

to something like this:

     i := QuoInt(a, y);    
     j := RemInt(a, y);

[Jan De Beule]

Done. All tests ran successfully.