The installshield| program version 6.3 seems to be driven by events:
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//
Function: Onfirstuibefore
//
Event: Firstuibefore event is sent when installation was run for the
Time on given machine. In the handler installation usually displays
UI allowing end user to specify installation parameters. After this
function returns, Componenttransferdata is called to perform file
Transfer.
//
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Onfirstuibefore () is performed the first time the installation is run on a computer.
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//
Function: Onfirstuiafter
//
Event: Firstuiafter event is sent after file transfer, when installation
is run for the "the" "the" given machine. In this event handler
Installation usually displays UI that would inform end user
Installation has been completed successfully.
//
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Onfirstuiafter () runs after a file copy is completed.
