Maybe I'm missing something, but the change seems quite simple:

my @data = /(!.*?!)/g;
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Gives:

Splitting data by comma as a delimiter
Data splitted is as below
!A001ST!==>!98!==>!1!==>!01/10/1999!==>!EUROPEENNE!==>!0!==>!EUR!==>!6
+!==>!7!==>!0!==>!98!==>!1!
Data splitted is as below
!A001ST!==>!AD,CD!==>!1!==>!20/05/2004!==>!ANDORRA!==>!0!==>!EUR,USD!=
+=>!6!==>!7!==>!0!==>!AD!==>!1!
[download]