First off, i deeply apologize for not figuring this out on my own. I've read several related topics including the FAQs but something is missing me.
I have:
[Halo 02] Pretty Hate Machine
[Halo 03] Head Like A Hole (US)
[Halo 05] Broken
etc.
I want to move the [Halo ##] string to %comment%.
I know this must be dead easy to figure out but i'm just not being able to.
Thanks in advance! 
I tend to say, that you have not done your hard work of searching in the Mp3tag history too much.
Your request sounds not to be a new one. Rather similar to hundreds of other requests. What it makes a little bit special is the usage of the square brackets, but possibly it may no difference, a closer look will help to decide what is qucik, what is easy and what is the best way for you.
So to begin, tell us what name has the tag field, which carry the above mentioned text strings?
Is it a TITLE tag field or it is a file name, or what? Do you need the square brackets to be in the COMMENT tag field too?
DD.20110225.2218.CET
Hey DetlevD!
As i above mentioned, i really do apologize to be redundant with my request. It's just that sometimes my mind spins around such simple tasks and i can't seem to figure them out on my own.
I just want to move the whole [Halo XX] thing to %comments% field.
Thanks for your attention!
He ... I still do not know what the origin tag field is, so I assume it is the TITLE tag field.
I hope you are able to adapt it to your needs?
As usual - there are many ways to do so in Mp3tag.
To go the easy standard way you would use the ready made converters and user definable action groups, normally it would cost two or three basic action steps to solve this task, not so heavy for the user, this is what Mp3tag makes so powerful. You should learn to use the action toolbox to solve your problems at your fingertips.
As usual - there is also a tricky way.
For example, use an action "Guess values".
And this works too ... with action "Guess values".
Sourceformat: $replace(%TITLE%,'[','[[',']',']]') Formatstring: [%COMMENT%] %TITLE%DD.20110225.2308.CET
Thanks but it doesn't work. I want to move "[Halo XX]" from the %album% field to %comment% field. That simple i guess...
That's your point of view.
Well - it does work - I've checked it in practice before publishing.
Yes it seems so, but that's your turn.
DD.20110225.2324.CET
I'm not trying to belittle your knowledge nor trying to create bad mood between us.
I'm just saying that i've both of your methods more than once and it just didn't work. Thanks anyway for your time.
Mostly Mp3tag actions do not work better when they "run more than once".
Usually an action should give the wanted result by the first run or never.
Sometimes it happens that repeated runs of the same thing does not harmonize with the goal of the user, sometimes crazy unsensible working will result in mangled data or badly loss of data.
You should learn to read posts and understand questions and give reponse just in time.
Also you should copy, letter by letter, the given instructions - without making errors.
Or just even better, try to understand and learn the Mp3tag philosophy and the toolbox to become a do-it-yourself Mp3tagger!
Have a nice weekend, though.
DD.20110226.0000.CET
Jesus Christ where's my head at...
I was trying to make it work without replacing the %title% for %album%, that's why it wasn't working.
I owe you an apology once more. I do have attention disorders.
Many thanks once more!