All good ideas, thanks.Looks good and simple.
When adding entities it would be nice to not have to click in the name box but have the cursor start there. It starts with the OK button selected. It would be nice if hitting the enter key was equivalent to pressing the okay button - right now it's one extra tab after entering the initiative number. It is handy that hitting esc cancels the entry box.
Saving and loading encounters would be nice so that they can be set up in advance. Same with saving and loading the adventuring party.