When did tag.proofcore.com go off offline? no where to download wallets 
TAG wallets can always be downloaded via these links:
Pools:ABCDEFGHIJKLMNOPQRSTUVWXYZ
| Wallets: Client Version TAG-v2.0.0.build-g-bdb-gcc
| Explorers:
|
Markcap, Analysis and information pages:
- CoinGecko - https://www.coingecko.com/en/coins/tagcoin - TAG Original
- CryptoCompare - https://www.cryptocompare.com/coins/tag/overview/BTC - only polls TAG
More information can always be found in this thread link: https://bitcointalk.org/index.php?topic=5128798.0