Hi.
After looking to Benge10's route and session and having reproduced his problem not being able to save a 47th path inside his tower, I can confirm that it is due to a script timeout while saving the tower data, timeout due to too many datas in the tower to be saved before reaching the script timeout threshold.
It appears that both standard ITs and EITs (EITs reuse the same routines as ITs to save/restore the IT internal data) have a usage limit which is more the total number of path objects definition for all paths in tower than the number of paths inside the tower.
From several tests, a total number of 600 path objects (60 paths with an average of 10 path objects for each path, or 30 paths with an average of 20 path objects for each path, … ) seems safe for save/restore operation of a tower. Above you may encounter some script timeouts that will break your tower data. In case you encounter such problem, the better is to quit your session without saving anything and reload your last session saved data loosing all the modifications done since this last save operation.
Next EIT version (v52 that should be delivered to DLS mid August or begining of September) will include in the enhanced IT manager tower pages a display of the current total number of path objects for each tower, with a warning message if this number exceeds the advised value of 600 path objects for all paths in a tower.
It is much more performant and safe to have multiple towers with short paths with not too many path objects objects than to have only one tower with some very long paths with a lot of path objects in each path.
Remember also that with EITs a path exit signal can be a path entry signal inside another tower, so that you can have successive paths belonging to adjacent distinct towers (no overlaps between tower).
Hope this helps.
Regards.
Pierre.