How to configure highligter

I try to build a own highlighter setup. I need only to colour text parts starting with an "@" and ending with ":" like "@x:" or "@ww:" (all without quotation marks). No comments, no numbers and so on.

I try this:

;PSPad user HighLighter definition file
[Settings]
Name=Meins
HTMLGroup=0
Label=0
FileType=*.txt
CommentString=
SlashComment=1
SlashComment=1
IndentChar=
UnIndentChar=
TabWidth=4
DoubleQuote=1
EscString=0
EscChar=\
CodeExplorer=ftUnknown
DocComment=
[KeyWords]
@a:=
@v:=
<iso>=
[ReservedWords]
[KeyWords2]
[KeyWords3]
@z:=


but it did not work. Any help?
Thank you.