Форумы / Cotonti / Extensions / Math Captcha

Hello,

I have one question about MCaptcha. For registration everything works great so I have wanted add the mcaptcha to forum newtopic. I have though it works as plug-in so I add files to plug-in.

mcaptcha.newtopic.tags.php and mcaptcha.newtopic.validate.php

and edit them as:

Code=mcaptcha
Part=newtopic.tags
File=mcaptcha.newtopic.tags
Hooks=forums.newtopic.tags
Tags=forums.newtopic.tpl:{USERS_REGISTER_VERIFYIMG},{USERS_REGISTER_VERIFYINPUT}
Order=10

and

Code=mcaptcha
Part=newtopic.validate
File=mcaptcha.newtopic.validate
Hooks=forums.newtopic.add.first
Tags=
Order=10

{USERS_REGISTER_VERIFYIMG} and {USERS_REGISTER_VERIFYINPUT} are present in forum.newtopic.tpl (is green in admin tool)
and plug0in was uninstaled / reinstalled but hooks doesn't work.

Is there possibility to use this plug-in like that or not?
Have I insert captcha code to forum site or plug-in is enough?

Every tips are welcome, thank.