"Filename - Tag" ICON

So, for copying "filename" into "title" [with mandatory correction] I have to use groups, because whatever [because I didn't get the explanation the first 3 times I read it]

And to this previous solution of mine I've made and an error preventing improvement:

Format value "TITLE": %filename%
Replace "TITLE": ".." -> ":"
Replace "TITLE": ":." -> "..."
Replace "TITLE": "
" -> "/"

%title%

Is that what yo are asking? [For me, a mask is that thing from Photoshop]. I have only that in the "Tag - Filename" icon, which works by just omitting illegal characters. Which is not good enough

Yes, that's what I want, but not an underscore for every sign that is illegal for Windows, but an underscore for a specific illegal character

And that is why I am talking from the beginning about two characters
:
/
Because I use them as a two separate examples [cases, problems] and because I can't have underscores running all over filenames [because I won't be precise enough]

That is the problem in the long shot and with thousands of files: the backtracking

That is way I've choosed a long time ago to "translate" illegal characters into legal

If I have an "/" in TITLE, a always use "_" in filename
If I have an ":" in TITLE, a always use ".." in filename
etc.

So everytime I copy between filename and tag, I have a potential correction to make

Yes, filenames are mainly for system and tags are what really matters for concerned / serious users

But filenames are also the fail-secure: a sometimes used safety information. And that is why I came up with the translation system. And I have just to much of an empirical experience backing that up, to not to use it anymore

So now now I need to automate that system, to make it easier and more precise

As I understand, we have covered the "filename" ---) "title" way: I have to use groups [because whatever]

Now for the "title" ---) "filename" way: what do I put in "Tag - Filename"?; or will I also have to use groups? If I put

$replace(%title%,/,_,)

it only works for the "/" sign; which is what I want. But that doesn't deal wit the rest of my "translation system". And if I put something like

$replace(%title%,/,_,)(%title%,:,..,)

or

$replace(%title%,/,_,:,..)

or

$replace((%title%,/,_,)(:,..))

it just doesn't work