Branches in AMD64 assembler

Hello,

after reading the gforth manual, the list archive and the 
comp.lang.forth newsgroup I was unable to find any documentation or an 
example with a loop in ASM64 and ABI-CODE.
I expected something like this:

ABI-CODE TEST
    0 # R10 MOV
L1:
   1 # R10 ADD
   10 # R10 CMP
    L1  REL)  JNZ
   RET
END-CODE

This gives a compile error

In the file testasm.fs is see :  HERE REL) JNZ
this gives no compile error, so I am close
can you give me a hint or an example on how to implement this?

Thanks, Anthony