It looks like the belt conversion tool sometimes is flipping one of the undergrounds in a set of underground belts whenever used.
I do not know if this is only with specific configurations or not
Hi there! I am aware of bug when some underground belts flip their direction. But i am think this is because how game scans selected area. Ill try to fix these bugs asap.
Hi! In new version of mod I fixed a bug with splitters, now they keep their filters and priorities on conversion. But bug with underground belts still persists.