TMS Intraweb grid does not “remember” javascript operation result

Question

Q1 In a TMS Intraweb db grid. I set three columns as ctdyncheckbox. Those columns are mutex. If one checkbox is checked, the other two in the same row are unchecked. I set clientevents ->dyncheckclick as below:

if (ctrl.checked && c==2 )
{( document.getElementById("G0D" + r + "C" +( c+1 ))).checked = false;
 ( document.getElementById("G0D" + r + "C" +( c+2 ))).checked = false;
 }
if (ctrl.checked && c==3 )
( document.getElementById("G0D" + r + "C" +( c+1 ))).checked = false;
( document.getElementById("G0D" + r + "C" +( c-1 ))).checked = false;
}
if (ctrl.checked && c==4 )
( document.getElementById("G0D" + r + "C" +( c-1 ))).checked = false;
( document.getElementById("G0D" + r + "C" +( c-2 ))).checked = false;
}

On the first page, click checkbox in column1, click checkbox in column2, click checkbox in column3, only one checkbox is checked, everything seems all right. However go to the next page, and then go back to the first page, all three checkboxs are checked !? It seems like the grid only "remembers" the manual click, the js operation result does not post. Why is that?

Q2 I set three columns as ctbutton. I want when I click one button, the other two buttons status change, such as change the buttons caption or color, but I can't find an attribute such as cell[c,r].button.color How to set a cell buttons caption or color?

intraweb 9.0.42
delphi 2007
 TMS IntraWeb Components 4.9
firefox 25
win8.1