Just following the instructions:

Make sure that you have Solana locally in localhost and change all the devnet references to localhost

$ npx anchor localnet
Workspace configuration error: Cluster must be one of [localnet, testnet, mainnet, devnet] or be an http or https url

What I ended up doing was setting this in my Anchor.toml - I'm not 100% sure it's correct (I have little Anchor experience, hence not sending a PR) but it worked:

[programs.localnet]
solana_svelte_counter = "C7SGr2s3HdBuEveTahL9H3CsXQDwxkYEUSRPeJAVeDN5"

[registry]
url = "https://anchor.projectserum.com"

[provider]
cluster = "localnet"
wallet = "~/.config/solana/id.json"

[scripts]
test = "mocha -t 1000000 tests/"

Does that sound correct? If so let me know and I will add the to the PR I will send - I have a bunch of small fixes to contribute! 😊