Endpoint Encryption

Is there a way to load a installation package that was created or to create a instillation setting template? I would like to make some changes to a current installation package but do not want to have to go through all of the steps again.

I'm not aware of any supported manner of directly unpackaging, amending and repackaging the exported MSI packages to change the settings within them, I'm afraid.

What's your use case for this?  The vast majority of the settings can be managed via policies anyway, have you considered using those instead (see below)?

http://www.symantec.com/docs/DOC9133