In order to use custom editors for the Grid you need to ensure that the components are configured correctly. Please examine the following example that illustrates how you can implement the behavior.
Furthermore, you can find the following article interesting that describes using editor templates in more detail.
Regarding the filter appearance. This may be caused by some custom styles or if some of the styles are not loaded correctly. Please remove any custom styles that are applied on the page and see if the behavior changes.
Also, make sure that the styles and script files you are using in the application correspond to the version of Kendo.Mvc.dll that is referenced in the project.
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