Difficulty in izap-videos plugin

I tried to activate izap-videos plugin and it activated but there are few problems-

1) It is affecting files. It shows no preview images in files.

I tried to find the code and found the no preview image code in /mod/izap-videos/views/default/object/izap_video.php

Even after editing the code in that file, nothing happened.

I even tried to delete that plugin and re-install it, but there was no solution.

I deleted the no preview image from graphics, but still, it effects the files.

2) I tried to use that plugin with api, and that is working properly. But, when i chose to add videos through my server or you tube channel, it is not showing any option to upload videos through that method.

I am using izap-videos-5.1.1

can any one tell the solution ?