The problem ZkScore solves

ZkScore aggregates verifiable proof of personhood thanks to integration with Proof Of Passport - privacy friendly KYC based on the ZK tech. It also includes dynamic, configurable score based on off chain and on chain trading activity like amount of transactions, gas spent, withdrawals from CEXes thanks to integration with ZK mail.

Challenges I ran into

I was able to fetch KYC data from Coinbase and notarize it using TLS Notary, however the project is not production ready yet so proving data for websites other than twitter which was used in a demo is not working correctly.