I got a problem with the TabPanel, Grids and Form
when I open New Tab first time everything is ok, but when I close this tab and open again grids and form don't show up

This is my code: stronadomowa.com/sp_exp/sp_exp.rar

Here's a screenshot of it:

when I open first time

and wen I open again

Link to Online Demo: stronadomowa.com/sp_exp

Thanks for helping me...