easy way to transfer '()' in title to comment field?

It is not clear what you want, because you speak about 'transfer' or 'add' some text from one tag-field to another tag-field.
Following there are some variations about the theme ...
"Copy or move text, which is enclosed into round brackets, to another tag-field"

  1. Move text from tag-field TITLE from within round brackets including brackets to tag-field COMMENT and delete this text part from the tag-field TITLE.

1.1.
Action #1
Actiontype 7: Import tag fields (guess values)
Source format __: $replace(%TITLE%,'(','((')
Guessing pattern: %TITLE% (%COMMENT%

1.2.
Action #1
Actiontype 7: Import tag fields (guess values)
Source format __: $replace(%TITLE%,'(','((',')','))')
Guessing pattern: %TITLE% (%COMMENT%)

  1. Copy text from tag-field TITLE from within round brackets including brackets to tag-field COMMENT.
    Tag-field TITLE remains untouched.

2.1.
Action #1
Actiontype 7: Import tag fields (guess values)
Source format __: $replace(%TITLE%,'(','((')
Guessing pattern: %DUMMY% (%COMMENT%

2.2.
Action #1
Actiontype 7: Import tag fields (guess values)
Source format __: $replace(%TITLE%,'(','((',')','))')
Guessing pattern: %DUMMY% (%COMMENT%)

2.3
Action #1
Actiontype 5: Format value
Field ______: COMMENT
Formatstring: $regexp(%TITLE%,'^.((.+?)).$','$1')

  1. Append text from tag-field TITLE from within round brackets including brackets to tag-field COMMENT.

3.1.
Action #1
Actiontype 5: Format value
Field ______: COMMENT
Formatstring: $trim(%COMMENT%' '$regexp(%TITLE%,'^.((.+?)).$','$1'))

3.2.
Action #1
Actiontype 5: Format value
Field ______: COMMENT
Formatstring: [%COMMENT%' ']$regexp(%TITLE%,'^.((.+?)).$','$1')

  1. Prepend text from tag-field TITLE from within round brackets including brackets to tag-field COMMENT.

4.1.
Action #1
Actiontype 5: Format value
Field ______: COMMENT
Formatstring: $trim($regexp(%TITLE%,'^.((.+?)).$','$1')' '%COMMENT%)

4.2.
Action #1
Actiontype 5: Format value
Field ______: COMMENT
Formatstring: $regexp(%TITLE%,'^.((.+?)).$','$1')[' '%COMMENT%]

  1. Delete text from tag-field TITLE from within round brackets including brackets.

5.1.
Action #1
Actiontype 7: Import tag fields (guess values)
Source format __: %TITLE%
Guessing pattern: %TITLE% (%DUMMY%)

5.2.
Action #1
Actiontype 5: Format value
Field ______: TITLE
Formatstring: $regexp(%TITLE%,'^(.?)\s((.+?))(.*)$','$1$3')

DD.20131221.1007.CET
DD.20131221.1900.CET Edit