Developer support is handled through the Click & Pledge forum.
To register for the forum use this link:
http://forums.clickandpledge.com/register.php
Once you have access to the forum you may post your questions here under the appropriate header.
http://forums.clickandpledge.com/forum.php
API Reference Materials:
Manual:
http://manual.clickandpledge.com/API-Platform.html
Forum Articles:
http://forums.clickandpledge.com/content.php?r=125-API