Default [Q] LG E400 - Mobile data not working with any custom ROM

I'm on O2 Pay & Go, and I've tried out different custom ROMs now - and my mobile data refuses to work with ANY of them.

- CyanogenMod 9 (latest nightly)
- AOKP Stable 1
- Cyanoid (Builds 10 and 11)

I've checked my APN config xml file in /system/etc and my APN is not stored in there. I've tried setting up my APN from Settings, but when I hit Save, it just DOESN'T and APN list comes up blank. I've also tried restoring default APN settings (Settings just crashes after a while when I do this), making custom XML files with my carrier data in them, and nothing works.

Can someone help me? This is driving me nucking futs and I really don't want to have to revert to stock.

Current ROM: Cyanoid 10 (android 4.0.4)
Kernel: gellmar OC (NOT sdmerge)
Baseband: v10Q