Hello Crate
Thanks for expressing interest. I'm glad to see that this idea hasn't totally died yet.

Regarding previously acquired injuries it won't heal them.
When a magatama is ingested it will take a blueprint of your body and memorize it. From that point on, any injury you sustain will try and recover itself to the point the magatama was ingested. This allows for the growing of missing limbs and the absence of ghastly scars.
 
If you'd like to include pre-ingestion healing. (Eg; A blind person being able to see for the first time) that can be included in the RP through other means).