Hi Brett,
GUI Composer generates .ccxml file based on device/connection settings stored in .appsettings file. However, there is a way of overriding this by providing a appConfig.ccxml file in your app folder. i.e. Configure a .ccxml file in CCS Setup Editor, make necessary setting adjustments, then find the file on disk and copy it to your webapp and rename to appConfig.ccxml. This will override the settings contained in .appsettings file. This also disables drop down widgets in Initialize page of your web app as you have now "hard coded" connection/device settings.
This is probably not applicable to your device/application. However, just in case, in the past when working with stellaris devices (both M3 and M4) I had to perform a system reset before loading a program otherwise the motor control application I was working with did not work. However, it would not work from the very beginning, thus it seems to be different from your case. Unfortunately, I do not know what the issue might be with program crashing.
The command that I used is
session.expression.evaluate("GEL_AdvancedReset(\"System Reset\")")
and it would need to be added before program load in appInitScript.js file.
Martin