Colors not changing automatically

[Estes0171]

   
Up until last night when I would go and select colorize or any of the color option it would change colors as I selected the color or slid the sliding bar to desired look the hit ok. Now when I do any of those actions the colors don't change until I hit ok which makes it hard to get the color I'm looking for unless I make multiple attempts so did I somehow click something to cause this or is there some type of bug? it does it on all images and I have uninstalled and reinstalled Gimp to see if it fixes the issues and stil does it/

[Tas_mania]

Is the 'Preview' button checked on the colorize box? (you can't see the box in the image)