Dear @mary and all,
This is a small one, but one of the annoying and time consuming things that happens in layout mode, is to accidentally activate a detail and then “zoom in” to it, thereby throwing off its scale. If you have dimensions on the layout side, you then have to carefully align the model with those dimensions. I wonder if its possible to have a visual"signal" when a detail is locked or unlocked. For example, the rectangle defining the detail could be red (when locked) or it could have a tab in one corner with a padlock symbol on it – or both. That way – you are visually warned when you have left a detail unlocked.
The other nice thing would be to be able to lock and unlock a detail with an alias, rather than having to go in to properties and find the little box and check or uncheck it.