Hello Worrorfight,
Our module does work on version 1.5.5
The error you are getting caused by the fact that you are not entering the widget code correctly. Please follow the following points to set this up:
1. Login to your Paymentwall account.
2. Direct to the widget tab of the designated project.
3. Confirm the widget code ( p1_1, p10_1.. etc)
4. Copy this widget code (i.e: p1_1, p10_1 into "Paymentwall Widget Code")
After this, the widget should work.
If you still have any questions, please go through our document on XenForo carefully
https://www.paymentwall.com/en/documentation/XenForo/1515
or mail to
devsupport@paymentwall.com so we can assist you further
