To distribute my program (http://tea-editor.sourceforge.net/) for Win32 I wrote the NSIS-based installer. I bundle these Qt-files into the installer:
Qt Code: 
  1. QtCore4.dll
  2. QtGui4.dll
  3. QtNetwork4.dll
  4. QtScript4.dll
  5. QtSvg4.dll
  6. QtXml4.dll
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Also I need to note that all resources (icons, images) are included to the binary file.
When I'm running the program on my PC, all icons and images are visible.
When other people installs my program and run it on another machines, they do not see icons on the buttons and images on QLabels. But, the QTextBrowser shows images well, and QMovie works too.
I've tested my program on another machine, where Qt is not installed, and I notices the same weird things - no icons on buttons, etc (see the upper text).
As I can understand, I need to bundle some additional Qt files with by installer? I've tried also bundle qgif4.dll, qjpeg4.dll, qmng4.dll, qsvg4.dll from Qt's plugins dir, but the result was negative - no icons.
What you can suggest?