Glad I stumbled onto this - ctrl-f8 is 'puffect' - but there are some 'errors' here (which, I hasten to add, have absolutely nothing to do with Goldilocks or Brian Postow).
1) "Under Workspace Appearance and Behavior -> Workspace Behavior -> Screen Edges" - No! That's not right. Since April 2014 when Goldilocks wrote this, KDE has changed the Systems Settings screen so that there are now two buttons - "Workspace Appearance" & "Workspace Behaviour" (at least we Brits get a correct spelling sometimes - although not, apparently, where Goldilocks come from)
This - the changing of the buttons - may not be an 'app-killer' but it is disorientating. I have absolutely no doubt that when Goldilocks wrote this it was correct; but, 18 months later it is not!
2) "Putting a 'Task Manager' widget in a taskbar (Panel?) configured to only show applications on the current desktop. This comes with a weeny, featureless little pager of its own.." - I use, and have used for years, SuSE. The cluster of blobs for the 'Virtual Desktops' has always been installed by default, has always appeared at the LHF side of the Panel (this section used to be called 'Icons' it may now be called 'quick start' or something.) and, yes, this may have 'been a weeny, featureless little pager' in April 2014, but it's not entirely true now; the 'cluster of blobs' do now show a (sort of) useful snapshot of what each window contains.
3) "Under Workspace Appearance and Behavior -> Workspace Behavior -> Screen Edges you can pick a corner or edge into which you can shove the mouse cursor to "Present Windows, All Desktops" - Um, no, it doesn't. I've fiddled around with this for some time and can't get anything to work.
I don't blame Goldilocks or Brian Postow, so, who do I blame? Well, KDE. I have used SuSE since 6.3 in 1999 (probably before that but 6.3 is my 1st 'boxed set') and I have always used KDE but why do 'they' (KDE) change comparatively simple things so frequently?
People like Goldilocks write good answers to perfectly reasonable questions but, 18 months later, they're out of date. OK. the correct answers may not be difficult to find; but finding them is irritating and for a tyro user (I hate the word 'newbie') it might be a 'deal breaker' (back to Gnome!).
Anyway, for the time being, Ctrl-F8 is good enough for me.
Thanks!
dmk