Filter error and incorrect positioning of drag handle  #13

Hello. Firstly, thank you for sharing this nice script.

I was playing with it all day, and got some problems.
Script successfully append items, resize, drag & drop, all good but on filtering I got "Uncaught Error: Gridifier error: too wide(ver.grid)/too tall(hor.grid) item".

Also, when clicking on a handle for dragging, some children elements get outside the item.

Any idea? Thanks.