Erro ao rodar npm install e start: npm WARN tar ENOENT: no such file or directory, open

Olá pessoal. Estou começando a aprender Java Script. Estou tentando rodar uns arquivos, mas aparecem alguns erros. Baixei 2 arquivos no GitHub, e em um tutorial simplesmente fala para manda os seguintes comandos:

npm install
npm start

Acontece que o resultado são várias linhas de erros, e é basicamente escrito "no such file or directory, open" e a indicação de vários aquivos, mas destes arquivos indicados realmente não são da pasta que estou rodando o programa.

Primeiramente eu instalei o installer do Node.JS. Depois abri o PowerShell do windows e andei até a pasta do arquivo. Lá na pasta tem o package.json. Mandei o comando npm install e saiu o resultado:


PS A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master> npm install
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-util-4d3ef4a2\LICENSE''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-account-3f4c6ed2\package.json''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\eth-sig-util-9b4fcb97\package.json''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-tx-239a6da7\package.json''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-util-7ebce322\LICENSE''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-account-3f4c6ed2\.travis.yml''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\eth-sig-util-9b4fcb97\.npmignore''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-tx-239a6da7\CHANGELOG.md''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-account-3f4c6ed2\CHANGELOG.md''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\eth-sig-util-9b4fcb97\README.md''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-tx-239a6da7\fake.js''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-util-b6b4bd9f\dist\account.js''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-account-3f4c6ed2\index.js''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\eth-sig-util-9b4fcb97\index.js''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-tx-239a6da7\index.js''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-util-b6b4bd9f\dist\bytes.js''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-account-3f4c6ed2\README.md''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\eth-sig-util-9b4fcb97\circle.yml''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\crypto-browserify-682e352b\example\bundle.js''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-util-b6b4bd9f\dist\constants.js''
npm WARN tar ENOENT: no such file or directory, open ''A:\yEarn.finance\github\iearn-finance-master\iearn-finance-master\node_modules\.staging\ethereumjs-tx-239a6da7\karma.conf.js''

[...]

Os arquivos que baixei: 
https://github.com/iearn-finance/iearn-finance
https://github.com/iearn-finance/itoken

Como resolver isto?