This is very serious issue. I've seen huge architectural companies were placing their model in real world coordinates (real Z, true North) following UK national grid system (origin is somewhere in La-Manche) and as a result - about 200 workers did struggle several years with their projects, as they experienced far form origin problem, errors in IFC geometry export, non-working tools (disappearing curtain wall panels), jumping MEP elements an so on. Switch to 64 bit did help to handle the problem, but still it is not recommended to place a model in real world coordinates - as any glitches can appear unexpectedly.
Also project orientation in real north cause several problems (when building is rotated and north is always on top):
1. Walls can have problems with 90 degree angles - like 99.80, 98.20 etc. Just because user will rotate the view with not enough precision.
2. Models for library parts or lines for new fills will always be rotated.
3. Cutting planes will not work properly.
4. Details placed on plan will be rotated too.
To manage all these issues will turn work in one big endless nightmare or real world coordinates.
Strong recommendations are: to place building next to project origin (I always place the way, that project origin would be in the centre of the building), use 0.00 for ground floor level, place building orthogonally - with the same rotation how it will be placed on plan layout (let say general arrangement 1:50, as site plan can show building rotated). Set project's sea level.
Topographical survey needed to place in relation of building and project origin (it's better to place DWG on separate worksheet and use Trace and Reference on the ground floor plan). And after it is possible to set world coordinates. There is special object called "Survey Point" in Built-In library that helps to set real world coordinates and north direction, that can be used in IFC export.
Here are articles about it on Graphisoft web-site:
https://helpcenter.graphisoft.com/knowledgebase/25447/
https://helpcenter.graphisoft.com/knowledgebase/63066/
