hello, i helped with the new captcha plugin code on latest virtuemart to get it impletemented, so that VM supports multiple captcha systems, if you'd like i can help you with your double captcha problem during EU business time, please contact me during the day at support (at) rupostel.com, i will need your:
- ftp access
- backend access
and i will check and fix this for you and report back to this forum on the issue and the fix.
best regards, stan, rupostel.com