Complex sentence: There is no wheelchair access to the southbound platform, the ramp to the northbound platform is steeper than 1 in 12, making it unsuitable for wheelchair users, and there is a large height difference from the train doors to the platform.
Split into simpler sentences: There is no wheelchair access to the southbound platform, and the ramp to the northbound platform is steeper than 1 in 12. Furthermore, there is a large height difference from the train doors to the platform.