I've gotten used to either wrapping it (get-item Code:\Mine\NewFile.ps1).FullName so that code (get-item Code:\Mine\NewFile.ps1).FullName works or changing into that PSDrivePath first CD Code:\Mine so that I can do code .\NewFile.ps1 as an example with an external app.

I think to get this working without doing either there'd need to be some form of auto resolving of PSDrive paths when passed to other executables like this.

Though I could be wrong on that