zero variance produced with low values

[GM-Crowley]

Hi
Let me add to others' comments about this great package. Although I am working through it slowly, it seems to be exactly what I need. One of the criteria is that independent variables cannot have zero variance. This issue is artificially produced by the package when variables have values between zero and 1, even if they have high variance. I solved this by converting km/sq km stream density to m/sq km (i.e. multiplying all values by 1000). It might be worth including this fix in the documentation, if not in the package itself.
Cheers
Gabriel