I'll answer as best I can 
1. This is by design. When you're first creating the new Power, it hasn't been assigned to anything yet (it's not part of the VPP). Effectively, there are no changes made to your character until you click the "OK" button and actually create the power/add it to your character. This is why the Real Cost is displayed.
Once you add the Power to the VPP, the Real Cost is changed (by the VPP) to 0. This happens as soon as you click the "OK" button in your example. When you go in and edit that Power, it is now part of your character (and known to be part of the VPP), so the Real Cost is shown appropriately....in this case, as 0.
Just as a note (I'm sure you've noticed): The Real Cost is displayed in the Power description for all slots in a VPP.
2. That's something that I'll be changing as we move forward, but for right now, it falls into the "it ain't broke, so don't fix it" category 
3. Sounds like a memory management issue on your system (internal to Java). What's likely happening is that, in creating the large character, you're creating a large amount of "garbage".....old/obsolete objects that Java has ready for memory reclamation. When Java needs to free up memory, it rarely frees up <b>everything</b>....it just clears out a chunk and then continues on. So, once you've filled up that virtual landfill, there's a lot more "churning" as your system clears small amounts of memory to make room for more objects....leaving the majority of the "junk" to just sit there.
As noted, restarting HD (restarting Java) will clear that right up, as the new Java session does not have any of the "residue" that the old one had.
This is one of the issues that I'm looking at as I go through the code in preparation for v2.....there are some things that I can do to manually override the default memory management that Java is doing.....hopefully if I do them at the right point(s), I'll be able to speed things up and eliminate this gradual slowdown that you're experiencing.
White Hats are for CISSPs
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