Performance issue when typing/filtering and moving an item/option to the other side

[sasaOvie]

Hi, I have the following issues. The items list contains 1000+ items/options. I am using version 4.0

Issue 1: What happens is that there is a delay of typing. When I type in a word (for example: HelloWorld), than the typed word is visible after a second or so.
Issue 2: Moving options/items from left to right when the list is large 1000+, than there is a delay of a couple of seconds before the item is moved.