1. Generic custom packs and firmwares do not carry icons, themes, sounds, etc that Operators' CDA handle like T-Mobile, Vodafone, O2, etc.
2. If you have a debranded phone (have Generic), you can use SEUS (remember that in most cases it upgrades CID to 53 but you already have CID 53 so don't worry) to search for a new update. It works for any phone, but the thing is that branded phones with firmwares or custompacks from companies sometimes do not have more updates like Generics do.