i tried to install qwt5.2.0 with Qt4.5.1(build with VS 2005). I install it as followings:
1. I put QWT in "D:\Qt\qwt-5.2.0"(the "D:\Qt" is where the Qt install) and modified the qwtconfig.pri to
win32 {
INSTALLBASE = D:/qt/qwt-5.2.0
}
2. qmake qwt.pro
nmake
3.Copy the qwt-5.2.0\lib\qwt.dll to Qt\4.5.1\bin; and copy the qwt-5.2.0\lib\qwt.lib to
Qt\4.5.1\lib.
4.Copy the "qwtplugin.dll" and "qwtplugin.lib" in the qwt-5.2.0\designer\qwtplugin\designer
to the Qt\4.5.1\plugins\designer.
5.Copy the .h files in qwt-5.2.0\src to the \Qt\4.5.1\include\Qt.

after that, i can use the QWT in Qt Designer.
question:
1. but when i compile the project with QWT widgets in VS2005, it doesn't work: all the .h file about qwt can't open.
2.when i compile the examples of the QWT as "qmake examples.pro",then "nmake", the error: fatal error

C1047:"Qt\4.5.1\lib\qtmain.lib" was created with an older compiler than other objects;rebuild old objects and libararies.



thanks very much for any device!!