GeoGen Script reference
GGE2703

The script attempted to use relative coordinate in context to which dimension of the map the coordinate is relative to could not be determined.

This means that relative coordinates can't be used with most functions of HeightProfile and some functions for HeightMap, like radius of HeightMap.RadialGradient. Relative coordinates can be converted to absolute coordinates using Number.FromCoordinate (which has an optional argument that specified direction of the coordinate). Point doesn't suffer from this issue, because each of the component coordinates has its direction well defined. HeightProfile.FromArray has a special optional argument only used to determine direction of any relative coordinates in the initialization array.

var map = HeightMap.Noise();
map.Blur(@0.1); // GGE2703, Blur applies in all directions at once.
var profile = HeightProfile.Slice(map, @0.3, Direction.Vertical); // OK, the direction is specified in the call