Hi Brian,
In the first screenshot, I think you used the “Relationship” button between boxes . The 2nd and 3th screenshots look familiar 
I usually just use the keyboard in Xmind, it’s pretty quick and using the mouse to move sub-topics around is a bit annoying sometimes.
* Use the arrow keys to move around
* Hit Enter if you want to add something below the current box.
* Hit Insert if you want to add something next to the current box.
* Just use copy/paste (CTRL-X, CTRL-V) to move a subtopic to another box.
It seems you can add relationships between different boxes but that’s something I never use…it makes things messy if you ask me. You can create a nice tree-like structure to cover all CCNA/CCNP/CCIE topics in a mindmap like this.