Follow the instructions in release notes to add firewall item back.
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SYSGEN_FIREWALL Is Not in the Catalog
To add the Firewall Service (SYSGEN_FIREWALL) to an OS design, you must do one of the following:
- Set the SYSGEN_FIREWALL variable at the command line.
- When you use the OS Design Wizard to create an OS design founded on the Custom Device design template, select Sample Firewall Service.
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Also check this thread.
Also (again!) check that you may need SYSGEN_NET_WFP and/or SYSGEN_DCOM as stated here if you installed the firewall and it won't work as expected.