Hi Zog,
Yes, having the curve separately on their own screen is super. HiLite Selection is probably the same as HiLite Curve if you click on one or more control points, then the affected areas on the image are overlaid with a green mask.
Recent Curves is located under the curves tab, however it appears to always be disabled I'll verify that this is the case, and add it to the bug list.
There are a lot of commands and options hidden in there - glad to see you trying some of them out!