.....plus lighting, drainage, disabled access, etc.
Well if its a simple platform you can just have a ramp for both normal and disabled access.
There is also already a suitable power supply because the platform will be adjacent to the preexisting streetlights heading towards the existing station. With a short platform (local door operation) you probably only need a single streetlamp to meet the illumination requirement.
As for drainage, given where it is it seems unlikely to flood, given its only a few metres from the sea, and if the sea floods it the line is likely closed anyway!
If they can justify Reston, they can justify reopening the entire Port Road route from Dumfries to Stranaer directly. Looking at Reston on a map the locals in Wellington, Cullompton and several other station campaigns must be wondering "why can't we get the Scottish authorities invovled?"
Well the cynical answer is that Reston was built to use it as a customs checkpoint after Scottish Independence.