Thanks for pointing out!
1. I reproduced your problem, and it is indeed different. For some reason, s+$ can match the last line of documents and one previous line from blank lines. Please use [[:blank:]]+$ instead, which should give you desired results. [[:blank:]] matches only horizontal white spaces while s can match both horizontal and vertical white spaces. I will take a look into this more closely, and see if I can fix this issue.
2. Create a simple macro like this (JavaScript):
document.HighlightTag = true;
Run this macro after reloading a Find in Files result file.
3. The search plug-in is somewhat premature since the source code is avaialble, and I am encouraging someone to extend this plug-in with more features. If no one is trying to develope the plug-in, I will consider doing that.
4. 5. 6. 7. I will consider your requests.
Thanks again!