That message just means a code was not generated when we hit your keygen URL. I had no problem getting this URL to work:
http://www.e-junkie.com/ecom/oplug.php?arm_level=-1&arm_keytext=sometext
Note that this forum adds spaces to URLs, so your URL should have no spaces in it. Maybe the -1 key level requires an 8-character keytext?
We don't really know much about the Armadillo keygen or how to configure it; we just obtained it from Silicon Realms, vetted it for security/stability, and installed it due to popular demand from sellers who lock their software products using Silicon Realms' SoftwarePassport/Armadillo solution, so if you aren't using that solution and don't have the documentation that would have come with it, we can't really help you get it working. It's really only provided for those who would already know exactly how they need to set it up.