II321 - DomSka is the end of a concurrency so needs a suffix; add point for where DomSka meets I14? After all, if you use the DomSka (which OSM marks as II321, presumably erroneously) point, you are highly unlikely not to use that road to the I14.
I've added a point to I14.
2012 GSV confirms II321 via the bypass. RSD map is not accurate enough here.
II329 - guessing OSM is wrong with the route at Planany
OSM is wrong according to RSD map, 2011 GSV, GM, Mapbox Streets, Esri WorldStreetMap and Here Hybrid Day. However, it might be possible that OSM is the only right one but there's no proof for it. Leave as-is.
II373Kon - Zar marked as II642 on OSM and Google, but I couldn't find any road numbers at all in the area
II374Brn - Rok is marked as II642 on OSM and Google, but I couldn't find any road numbers at all in the area
It's II373, not II373. II642 is indicated on RSD map (March 2016 and July 2018 version) but
2017 GSV has II373
twice at I42/II374 instead of II642. I guess that's the reason why I've not drafted it. Not adding but I've noted it to readme.md.