Hi!
As you suggest, producing a regular mesh, cleaning it, and using it as source data for the tiled model works well. It is the only way that I know of to achieve your desired outcome.
Regarding question 4 there are two different approaches I can recommend.
1. You can use the split_mesh script (exists for metashape 1.8, not sure about 2.0) to split the mesh inside the chunk and then build a tiled model for each part. Then use "merge tiled model" under advanced settings in the build tiled model settings window to merge the parts back together one at a time into a single model.
2. Create chunks either with the split_in_chunks script or manually. Then you can use the "merge chunks" option in the workflow tab where you can select tiled models which will merge them if they are aligned.
Hope this helps!
