I don't have CP7 anymore, support is difficult then.
However copy/paste is indeed a practice that could cause corruption. I'm not sure what you mean by 'text box: is that a Text Entry Box, a Text Caption or a shape filled with text? Why do you not use an object style for the objects? SImilar for the buttons, which type of button do you talk about: text button, transparent button, image button or shape button? All have an objec style. It is a better practice to use styles instead of styling an object, then copy/paste it a lot. If you need a text container in the same location for a lot of slides, create that container on a master slide and use that master slide to create slides. If you need a button on the same location, you can do the same at least with shape buttons. Or you can put the shape button on the first slide and time it for the rest of the project.
Object styles and master slides are part of the used theme, which you can save as a custom theme and reuse for future projects.
Personally I avoid copy/paste as much as possible. If I need several instances on the same slide, will use Duplicate (CTRL-D) which is not using the clipboard, contrary to copy/paste.