Could you please send the file via email.

I found the cause of the problem. It is in the project settings:

When importing PocketTopo data, CaveRenderPro assigns a device number to each survey leg - either the number
configured for 360° devices or for 400 gon devices. If both of these numbers are set to 0 in your project settings,
the import assigns device number 0 to every leg.

During the cave network calculation, a device number of 0 has a special meaning: it tells CaveRenderPro that the
coordinates of that leg are already known, and it tries to back-calculate length, azimuth and inclination
from the (not yet computed) coordinates. Since those coordinates are all zero at that point, the result is length = 0,
azimuth = 0, inclination = 0 for every leg.

Please let me know if you need any further help!