About the road warnings... i think they are a remains of the former autoroadtool which does not work anymore. Accordings to the road´s settings this tool would have avoided big bank and angle values. As far as i know is only the ai taking unwanted shortcuts sometime but thats not really related to the roads.
The road smoothing tool should "work" as always more or less because the roads are imported into visitor and handeled like any other road.
I´m really happy that some dedicated guys are working on these tools... thank you