Without seeing the instrument it is hard to say much, but the error  
message seems clear -- the table number is zero, which is  isuslevs is  
zero.
Check for typos?

Or show us the code

Quoting Stefan Thomas <kontrapunktstefan@gmail.com>:

> Dear community,
> when running a specific file, I get the error message:
>
>> INIT ERROR in instr 1 (opcode StefansglobalAdsyn): Invalid ftable no.
>> 0.000000
>> ipartsus        tab_i   #i14    isuslevs        0
>>
>
> The strange thing is, that the file compiles and I can hear sound.
> And all my ftables don't have a number!

All your tables have numbers somewhere, even if automatically assigned

The effect of the init error is to ignore the instrument - others will run
==John ff
> Thanks for any help
> Stefan
>
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