Peter,
We unfortunately have not been able to reproduce this problem yet.
1. Can you let us know the model of your player?
2. The scaled version of images are stored in the temp folder (C:\Users\Peter\AppData\Local\Temp\javaps3media). Could you look into this folder for jpg files (names will be long numbers) after playing one or more of these big images that these scaled images do exist? The images there should be viewable on computer.
3. Could you provide us with debug.log after playing these images?

Since the file is larger than 1920x1080, it should have been scaled. We are looking into it.

Dear Peter,

Does that large image file has dimensions less than 1920 and 1080?

Some players, e.g. LG and Pioneer, have problem playing large image files. Therefore, the PS3MS automatically resizes all images larger than 1920x1080 to 1920x1080. In most cases the images become much smaller than the problem size and they should play perfectly on the players.

This scaling, however, isn't applied if the image dimensions are under 1920 and 1080. If you are seeing this, can you send us a sample image using a file sharing site like mediafire?

Peter,
The new log shows problems which are likely cause of the image issue. We are analyzing it.

Peter,
The problem is caused by a missing run time library (Microsoft Visual C++ 2008 Redistributable). We will fix it in our installer program. Can you try installing this library from http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=... to see if it makes it work?

This confirms the solution. We will fix the installation so that this problem doesn't occur.