I use Webform Civicrm Integration to register multiple attendants to an event, and calculate the total fee. (This works fine).
I have included a Contribution Page, which provides the choice : Now on-line / Later.
"Later" works fine, but if I choose "Now on line", I get a page "Page www. ... .com does not work ; impossible to manage this request for the moment ; Error 500".
The Contribution Page refers to a CM-CIC Payment Processor (extension), but the "test" processor behaves the same.
The Contribution page alone (via "https://.../index.php?q=civicrm/contribute/transact&reset=1&id=1"), works fine.
It seems that sth is missing between Webform and Payment page