No Readme.txt

Installation
Copy module to /sites/all/modules so images set through css have right paths. Otherwise you'll have to tweak the css.

Download Plupload library and put it in module directory in sites/all/modules/plup/plupload.

Then go to field settings and set Plupload as widget. Only image fields are supported for now.
Plupload has it's own permission so go to the permissions and allow plupload for designated user roles.

As admin user, try to drag one .jpg into the box, browser (Firefox 8.0.1) nothing appears in the box. Older browser (Firefox/3.6.24) just opens the image.

Using the "Add" button, I can select multiple images, but I get popup:

Mozete nahrat iba 1 suborov.

Probably need that to be in English?

Here's a slightly better version for your install instructions:

Installation

1) Download the Plupload widget and put it in module directory in sites/all/modules/plup/plupload. (License Type GPLv2 is a free download)

2) Install Plup to /sites/all/modules so images set through css have the correct paths. If installed elsewhere you'll have to tweak the css.

Usage

Create an Image field, and select Plupload under widget. Only image fields are supported for now.

In the field settings, set "Number of values" to allow more than one image to be uploaded at time.

Plupload has it's own permission so go to the permissions and allow plupload for designated user roles.

And the Plupload library really ought to be in the library dir, but can't get the images set to private to display, so giving up. I think Media has the same general issues, you might check how they solved it.

Best,
Sam