According to my observations Ctrl+Z won't work after replacement [with Replace ALL] using regular expressions and wildcards (even when you don't actually use regex or wildcards but just have this option checked). Ctrl+H won't work when cursor is in the source half of the active segment. Ctrl+C won't work sometimes when the source half contains replaceables, as far as I understand Ctrl is reserved for replaceables insertion purpose - that is why you have to use 'Copy ' command from the drop list.

According to my observations Ctrl+Z won't work after replacement [with Replace ALL] using regular expressions and wildcards (even when you don't actually use regex or wildcards but just have this option checked). Ctrl+H won't work when cursor is in the source half of the active segment. Ctrl+C won't work sometimes when the source half contains replaceables, as far as I understand Ctrl is reserved for replaceables insertion purpose - that is why you have to use 'Copy ' command from the drop list.