Create proof-of-concept demo

Overview: I bought this tool: [login to view URL] In the middle of the page you can see a demo of this image editor. This demo, PHP-scripts etc. are included in the ZIP-file I got. Now I need a proof-of-concept demo with this editor on my own website. My Problem: If I scale down (resize) an image from 500 to 250 pixels to display it on the editor, and then when saving I scale it up (resize) again from 250 to 500 Pixel, it gets pixelated. Your job: I give you FTP access to my website where you find all files of the ZIP, so you can create the demo. STEP 1: The editor must load 2 images (red cubes) both with a size of 500 x 500 Pixel (72 dpi) They must be displayed in the editor with a size of 250 x 250 Pixel (144 dpi I guess...). >>>>> See screenshot attached how it must look like <<<< STEP 2: Add a button which sends the image of the editor (canvas) to the server where it must be saved (some scripts are already included in the demo zip). The saved image on the server must include both images (cubes) with the size of 500 x 500 Pixel (72 dpi) or 250 x 250 Pixel in 144 dpi. IMPORTANT: Point 1: I will test it with real images (PNG/JPG Pictures) with 500 x 500 Pixel. This project is not done if they are getting pixelated, see my problem description on top. Point 2: The user can move around the images in the editor >> that's the reason I want to use such a tool, so the users can do things/edit the images.