First post after a long while of lurking and developing!
1. Whenever you rename a bone in ME the text cursor (Caret) goes to the position of the last place the text cursor was at. So when you rename multiple bones, if the name of the next bone you are renaming is longer than the last position of the text cursor, the text cursor stays in the same place instead of say, going to the end of the string.
Just as a suggestion, perhaps it would be better when renaming a bone, have the string pre-highlighted after pressing Ctrl+M?
2. (I guess this would fit more under Feature Requests) Something that theoretically should be fairly easily implemented and would make EE more versatile is the following:
Say you have 2 versions of the same model in whatever format, dae/mesh,etc (Same skel/skinning/etc), one of which is say a human standing, the other say jumping in the air. After making a mesh of the standing model/importing the skeleton, it would be very nice to go to the animation tab, add the current pose as a keyframe and then import the pose/skeleton arrangement from the jumping model at a later time in the animation. Then after looping it, you'd have a jumping character!
This is would making working with Poser Pro/DazStudio much easier as it's skeleton exports make it incredibly difficult to animate any character in ME but makes up for it in neat skinning and skeleton building.
Oh and from everything I've done so far, you have created a spectacular engine Grzegorz! I plan on purchasing a license in the future