The ID numbers for people in your tree in Family Tree Builder, are internal to the programming of the tree, and are not editable.
Please note: you may notice more ID numbers than people in the tree. The reason for this is ID numbers are not re-used when people are deleted. Therefore, ID numbers can exceed the actual number of individuals in the tree."
I need to know this before I install V7.

(PLEASE!!!!!!) e.g. If I deleted, say 3 people because they were duplicated, and had ID numbers, say, 1123, 1124, 1125, those ID numbers can be used again?