OK. I've spent about a half week on this. Good news and bad news.
1 - Good news) I've identified, found and fixed a few memory leaks. These fixes will be incorporated into the next release.
2 - Bad news - or Jedi mind trick) These are not the leaks you are looking for. It is unlikely that what I found is what brought our SlickEdit memory footprint up to 2G. They were small leaks.
3 - resizing and drawing) Not leaks. We have a fairly significant line drawing cache. You are merely filling up the cache. The test project has a bit over 6000 lines of code, the cache holds 20000 lines before it fills and purges. This is just using memory, not leaking it.
4 - delete and undo) I did not observe a significant memory increase here, and the memory leak tracking software did not identify anything as leaked as a result of this test.
5 - searching) same story, yes, first time use of a feature can uptick memory somewhat, when the form is loaded the first time, etc, but no definitive leaks identified.
6 - segmenting) We have a our own memory allocator for speed. Like any allocator, it can fall victim to some segmenting depending on usage patterns. Some of the memory growth you see could be segmenting, well, it will appear as growth initially, but once there is enough memory in use, the growth will level off entirely. Note, this can happen with the system malloc() too, so there is nothing particularly wrong with our allocator, it's just faster than malloc.
7 - scrolling) see (3)
8 - caches) we have a lot of caches. Tagging especially has a lot of caching going on. It is one of the few things that gives you some limited control over the caches, yet, even there, there are some caches that will just grow as needed. You can't make a setting for everything. I have suggested ways to cut back the tagging cache earlier in this thread.
9 - your config) You were loading a mini-map tool that I did not have access to. Hence, this did not factor into any of my testing.
Hope this helps. I'm still digging around for leaks, as I work. Maybe something will surface eventually.