If you feel that the problem is caused by the update to iCamSource, you can try reverting to an earlier version. The current version (1.4.2.5) and the previous two versions (1.4.2 and 1.4.1) are all available at
http://skjm.com/icam/support.phpMake sure you uninstall version 1.4.2.5 before installing an older version. You can uninstall iCamSource by going to Control Panel -> Add/Remove Programs.
From your description, it sounds like iCamSource crashes after it's been running for a while (as opposed to crashing immediately on launch). That indicates that the prerequisites are installed.
Please make sure that Windows is fully updated using Windows Update. Also, make sure that your webcam and video card drivers are up-to-date.
Quit or disable all video capture programs, such as Skype. They might be fighting iCamSource for access to the camera.