Both .ros and .bos files come from a software called Dynamite VSP and are used for some kind of style data, but it doesn't seem very likely that some kind of ros to bos conversion is doable and we have actually found no information about such thing.
The software was eventually acquired by Autodesk and rebranded as Civil 3D and it is unclear wheter the original file types were adopted in the successor product as well.
Updated: October 16, 2023
This conversion entry was verified by us and conversion was flagged as wrong or not possible.
Usually this happens when the conversion would try to convert different types of data between each other, such as audio to image, or it is not possible because incompatibility between programs, caused by closed file formats, very limited support etc.
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