Thanks, good questions.

1. You might need the active key? I just used owner because I'm lazy :)

2. Hey there's a custom_json function https://beem.readthedocs.io/en/latest/beem.blockchaininstance.html#beem.blockchaininstance.BlockChainInstance.custom_json

I haven't tried this either but it looks legit. I was scared of messing up those transactions so I went straight API. I bet custom_json would work.

Edit: After thinking about it, (1) could be considered security issue so I issued an update.