[WB20] Controls inside Looper aren't working correctly

Good afternoon, I'm working with a looper that is having an odd behavior. I got an EDT with quantity of items and a plus and minus buttons, that just add and substract from it, but whenever I click any of those it doesn't do anything, it causes my page to "flash" as when clicking a button without ajax, and doesn't update the value in my EDT. The other control is a checkbox, everytime I click it, it checks and unchecks itself, also when clicking it it also makes an Image control to disappear and appear again. The checkbox doesn't have any code and neither does the Looper in any of it's events. The code for one of my buttons is the following:

LOOP_Carrito.EDT_Cantidad++
IF LOOP_Carrito.EDT_Cantidad > 1 THEN
BTN_menos..State = Active
END
IF LOOP_Carrito.EDT_Cantidad = 99 THEN
MySelf..State = Grayed
END

This is making me nuts! TIA