Hi Jean-Florent

As Tarquin said!

However solutions I have used to good effect...

If your data is pencil and paper, then printing and sketching on paper (while viewing models, plan and elevation on-screen simultaneously) then scanning those sketches can be an easier way of untangling.

Or break the survey into small sections of survey that only minimally overlap, and export one at a time for eventual sketching.

If your data is paperless, then the best option is to anticipate this while in the cave - if it is becoming hard to decipher in the cave on your device, then it won't be better in XTherion.

In this case, create a new survey file.

In both cases, limit the scope of your xvi only to the individual survey.

Good luck!

Bruce

PS: Perhaps a key thing to remember is that if the plan is becoming difficult, an elevation drawing will be a better way of conveying to viewers an understanding of the cave.

(An example of a 5 or 6 level shaft spiral that is somewhat OK in plan)