[Solved] Custom icon working, but dynamic icons not

I know this topic has been asked before, I think I read them all, but still not working.

I created a custom icon, put it in the proper folder (openhab-cond/icons/classic), made sure it was all lowercase and it is working great.
For dynamic items I thought I only needed to create an on and an off version which was indeed confirmed by the Tutorial that Thomas often refers too.

So I now have three files spotlight.png spotlight-on.png spotlight-off.png.

I call that in the items file with a definition that has worked

but it only gives me the basic ‘spotlight.png’.
I feel silly asking what I am doing wrong. no doubts something that will make me say why didnt I see that (a typo or something), but I checked and rechecked, can’t see what I am doing wrong.
Anybody any tips?

Let me add, I didnt re-define anything about the use of svg or png, because the png icon shows up (just not dynamic) so I presumed that was in order, especially since it also shows up in my paperUI items config:

have made sure bitmaps are now selected in the UI’s, makes no difference

I have no idea how, but hours later, after solving some other peculiarities, suddenly the icon did change.
Some of the other peculiarities I solved seemed linked to the use of notepad, a resave in wordpad restored that… and made the custom icon change dynamically