I've really missed the ability to color blocks of disabled code due to preprocessor directives for a while now. There was a thread on this quite a while back here:
http://community.slickedit.com/index.php?topic=158.msg4394#msg4394So I posted a feature request in the SE 2008 beta forum and Clark was kind enough to point out this was already possible and double kind for not calling me an idiot.
In any case, I ripped a ton of code out of SE v12 seldisp.e, replicated it in the attached defs_color.e file, and replaced some of the hide code with _StreamMarkerAdd color code. To run, load it up and execute defs_color() to color the code blocks. (Arguments should be eerily similar to the existing SE preprocess command.

defs_uncolor() should remove the highlighting. It currently uses the no-save color for the highlighting (CFG_NOSAVE_LINE) way down at the bottom of the file. This works well for me but should be fairly trivial to change if others don't like it.
I'm not experienced with Slick-C, so I very likely have done bad things(tm). But it appears to work on a bunch of the C++ files we've got, so perhaps this will be useful to some other folks after everyone points out the bugs and it gets fixed.