I use SketchUp for small models and then print in 3D.
To troubleshoot intersected in small dimensions (< 1mm), I tried to scale the largest and then reduce it to the end model (as they say on the forums) . But the problem remains the same. Because large-scale functions do well, but then there are problems to reduce error, SketchUp manages your way. Sometimes leaves gaps and I can not print.
Will they add some to work with small models ?.
What are you using to format your file for printing? You could try scaling your part down in that app.
If you modeled in large scale an it’s a solid model, it will be solid after making it smaller. Do you have an example model for us to have a look at?
Because of this problem with small dimensions I’m only work with meter units,never with mm.
So I start to design like 1m is 1mm, or import model in meter scale and when the model is ready for 3d printing I just export to STL in meter units.The STL file doesn’t have the units information so is the same file in mm or m.So I never need to scale the model.