I build kchmviewer from source, but find that it doesn't install icon.
The problem is due to KDE4_INSTALL_ICONS() in "packages/CMakeLists.txt". It only accepts some patterns of icon names.
Hence, to solve this problem, in "packages" directory, you have to change "kchmviewer.png" to "hi128-app-kchmviewer.png".
In that way, it installs the icon in "/usr/share/icons/hicolor/128x128/apps/".