Errors when closing split window with <CTRL-W o>

[determin1st]

If I split window with LS code:

:LiveScriptCompile watch vert

I have [ | ] a splited workarea and able to normally close generated JS code window with <CTRL+W c> - no errors here. But when I do <CTRL+W o> at LS code window, I have vim console output with "Press Enter" confirmation. There are several "Press Enter"'s.

Here is a screenshot of log:

http://i83.fastpic.ru/big/2016/1109/99/7b624dccbc7d2f8408e8124c7769d599.jpg