Yes,
So I still don't know why the plugin never appears in the category "Custom Widget" when I specify it, and I don't know yet why it appears in the 'Input" category when I specify it. For the moment I add it to "Input" ... I know it is not a clean solution but I don't have time to find out why for the moment.
About the usage of a plugin, I add it in my dialog with Qt Designer, then I add the header file in the implementation still with Qt Designer. Then with Visual C++ 6.0, I add the .cpp, the .h and the moc file of my widget.
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