in the original, the cap[tcha session is named captcha_Security_Code, the session is named bassed on the field variable in the captcha image string:
field=Security_Code
the new one has a different value:
field=Security_Code_1
so the captcha session is named "captcha_Security_Code_1"
to fix it, change:
field=Security_Code_1
to:
field=Security_Code