The picture representation using scale are different,
and with 50scale it show less size

Test case:
http://dl.dropboxusercontent.com/u/22524283/rpg%20maker/easy/Tests%20case%2001.rar
@gadesx the dropbox link is broken. Could you reupload the test case here where possible?
its impossible for me reupload that without internet in home, but you can make a picture similar and test with player.
added [Needs Feedback] until a new example is available.
I'm pretty sure I saw a while ago some prepared image that either showed an Apple or Nothing depending on the resize algorithm of the web browser used, would be a nice test case but I can't find it anymore.
The old test case, maybe works fine with actual player.
Tests case 01.zip
This was also noticed in #2133 for battle gauges. Leaving a note here
Most helpful comment
The old test case, maybe works fine with actual player.
Tests case 01.zip