Uploading Images With Redactorjs, Inserting Into Editor Fails

I use extension located here and It displays editor. I then use this extension to upload images and it does upload. The problem is, after uploading the dialog vanishes. When I reopen it there is no option to browse files I uploaded and insert them in editor.

I believe I'm missing something here because If I try YiiBooster's RedactorJs it presents those options but then I cannot make it upload files. Moreover, in YB's there is third method dealing with thumbnails but this extension seems to posses none (or I missed docs somewhere). I have no idea what to do next and I need help!

-regards,
Stefano