How to place Cpxinteractive ads code in phpbb forum?

I want to place cpxinteractive banner ad in my phpbb forum. I got the ad code in "iframe". But for some reasons i cant use iframe in phpbb forum. ie. when i place the ad code, it displays blank page. Im using phpbb 3 version.
If someone has experience with placing cpxinteractive code in phpbb forums, please help me. I shall be so much thankful to you.
Ps. phpbb support doesnt seem to help about this issue.

Original post by apple