bugs in the geometry app

[wangchong01]

hello,
i have found some bugs in the geometry apps,but how can i fix it?
1.when some point is on the curve defined by "conic" ,the point disappears when i am trying to drag it.
2.the function single_inter will not give a certain point when the curve is defined by "parabola".
3.it will take the calculator a few seconds to calculate the point on the ellipse when definition of the ellipse refers to other points (i.e. ellipse(GA,GB,GC)).

thanks.