Opal Hard-SPL: You need to flash this first to be able to flash whatever ROM you want (more info can be found in the previous link).
An English/WWE ROM that you like. If you want to stick with a stock ROM you can try the one here in this link (for the record, I haven't tried this ROM myself and I no longer have an Opal to test it) or you can try whatever custom ROM you like from all the ones available in the ROM development section
I replied here instead of replying to your PM so that other can benefit and/or correct me if there are simpler ways.
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