Are you sure these particular assets can be straightened in T:ANE? Bridges and some wall splines can't be straightened. Looking at the config.txt for Basalt wall shows just that. It's a kind bridge. If it's a kind track, with all the other qualifiers, to make it not a track or road, it can be bent. If they could and can't be anymore, it means that the type of asset is being enforced preventing this from occurring.
