console log report error, but example demo seems worked.

[alexshencn]

ERROR in /home/alex/node-project/react-visual-modeling/src/index.tsx
../src/index.tsx 6:8-13
[tsl] ERROR in /home/alex/node-project/react-visual-modeling/src/index.tsx(6,9)
TS2305: Module '"butterfly-dag"' has no exported member 'Arrow'.

i checked butterfly-dag on github, it doesn't export module named 'Arrow'.