I totally agree with David. I believe this to be an issue with auto-connect as well as snap to grid.  Please fix this.  Do not go the way of Visio or another alternative product will be sought.  when I drag and drop an object I do not want anything underneath to automatically move and attach itself to the object being dragged.  Thankfully if I move the object with the arrow keys rather than the mouse it doesn't happen or else I would have already binned Lucid.  Holding down cntrl whilst moving lines also seems to stop objects and lines snapping to grid (even though they should not snap at all as the settings for snap are disabled).

Hi David and Richard thank you for posting in the Lucid community! Our sincere apologies for the delayed response on this thread - I wanted to follow up in case this answer may still be useful to you and to provide a solution for other users who see this thread in the future.

The behavior you're describing sounds as though the Line Connections setting may still be at play. This setting causes objects and lines to "look" and "reach" for each other when in close proximity even if "Snap to Objects" "Snap to Guides" and "Snap to Grid" are all disabled. In my example GIF below observe the behavior of the line before and after disabling Line Connections. 

Once it's disabled you should be able to move the line entirely on its own without the presence or proximity of other objects guides or grid lines impacting it. If this is not the case please don't hesitate to let me know!