After drawing and selecting an object I change either the position or the dimensions, and hit enter. The object then adjusts to match my new changes. Then occasionally when I select a new object and click in the dimensions or position text box it will automatically mimic whatever changes I put in for the previous object. Example: Object one's height is is 12 inches I click on the text box and type "-5". The object shrinks and it's new height is 7 inches. Then I click on the y position text box and set it to 15. I proceed to draw object two. It's height is 3 inches and its y position is 4. Then the height text box is clicked on. Without typing, object two's dimensions are changed to 0 height, and a y position of 15. Ctrl Z will move object two back to y = 4 but it will remain height = 0.
Ive had to redraw many projects due to this issue.