It looks to me like your problem is elsewhere. One question I have is why you're using grep there. But the regexp does what it's supposed to. 
#shortened for clarity, but works with the full thing
$_ = '<*ra0*p(9,-9,0,9,0,0,g,"U.S. English")><Bz8>ATTN: Out of school 
+youth';
s/(<Bz8>)([^ ]*)/$1$2<\$>/;
print;

[download]
prints 
<*ra0*p(9,-9,0,9,0,0,g,"U.S. English")><Bz8>ATTN:<$> Out of school you
+th

[download]
on my system.

In reply to Re: Parsing Quark file with RegEx by Eimi Metamorphoumai
in thread Parsing Quark file with RegEx by rael9

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