When editing a set of network rules, you can “copy from” another application or another predefined rule. However, when you use this possibility twice, the newly copied ruleset replaces the existing one. It should be added to it instead.
Case in point: I’m building the ruleset for Windows Mail. It’s both an email client and a news (NNTP) client and an HTTP client for HTML messages (I’ve defined the appropriate predefined rules). It would have been nice if I could have copied the rulesets from all these predefined rules, then pruned the duplicates.
General suggestion: the user interface should be reviewed and reorganized with the assistance of a non-expert end-user. Right now it’s inconsistent and difficult to navigate.