To find out if the phone is locked, press the following key combination on the phone while its turned on. It doesnt matter what menu you are currently at.
Left, * button, * button, left.
This will bring up the menu where it shows what you have locked. It is the same menu where you enter the IMEI unlocked code if you can find it.
As to the customization, I believe you need that so the phone knows what languages to use within it. I don't think the phone will work properly without the customization, but I could be wrong. But you should have flashed 3 files (firmware, fs, and customization).