C# | CheckedListBox not responding / weird failure

Question

Hi,

I'm trying to use CheckedListBox with such parameters :

ColumnWidth=40
MultiColumn=true
Items={"Mon","Tue","Wed","Thu","Fri","Sat","Sun"}
Size= 282; 19
Enabled= true
Locked= false

So, it should be rendered as a horizontal strip containing days with corresponding checkboxes.

Rendering is okay, but the control is not responding to anything (mouse,keyboard,etc...) Seems weird, because all other controls on this form works ok, there is no other threads working in backgrounds, there is nothing that could interfere with this particular CheckedListBox...

Appreciate any answer...