Input-Elements are built with the “index” from the colModel.
But the search-trigger searches input-fields with the with the “name” from the colModel. Therefore, your “index” and “name” fields in the colModel must be exact the same. If there is a difference, filterGrid fails.
I am having the same issues as koni and he is right about the reason why it does not work. It works in previous versions but not it 3.5 beta. Thanks in advance for fixing this bug asap and for a lot of hard work that you've done.
Since for me is very dificult to reproduce this behaviour I will be very happy if someone send me a link to the problem. If someon send a link please to include the development version (not minified version)