Some standard Windows keyboard shortcuts are missing. In particular for me, I use my mouse on the left and use [ctrl][insert] and [shift][insert] in all my other programs to do copy and paste since they work well with the right hand. I still forget occasionally that I am in Schematics and that they dont' work.
Almost all Windows software accepts an input when the focus is moved to another field or entity. There are many locations in Schematics where you must press enter, or press an accept button, or move to another field within the particular group but the or's only mean that one or more of the above are acceptable but not the same from item to item. In standard windows use, moving the focus to any other part of the program will cause the data to be accepted. As an example, changing the name of a sheet in a schematic will only be accepted if you press the enter key. In most windows programs, clicking on another sheet, anywhere in the sheet, to a menu, or even another program moves the focus and accepts the input.