First of all, thanks for sharing this nice plugin!
When issuing Ctrl+p/n or [+I on some files (which ends with .js) I get the following error:
E121: Undefined variable: b:node_root
Error detected while processing function node#lib#find[8]..<SNR>233_absolutize:
line 7:
E15: Invalid expression: b:node_root . "/node_modules/" . a:name
The variable b:node_root is indeed undefined on the files which display errors. On the files where the problem doesn't ocurr the variable is defined.