Plist ask how to deploy and modify?

Local settings when processing applications using the plist parameter storage, ask the following questions existing:
app in plist program can be opened, but it was not released to the sandbox folder, can I modify and save them directly (or to copy to @ Document in operation)? < br />
Reply:
This should not be a
Reply:
In the bundle it is readable.
If you want to read or write operation, it is best to copy Document
Reply:
The app is in the main bundle plist, you can only read.

If you need to change, you can put in Documents
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If you want to modify, make a copy of the document directory

Reply:
plist are generally read-only