You’ll find video demos of form building based on openEHR templates in several of the pre-procurement videos listed at: Swedish openEHR platform procurement Q1 2020 They are not PDF forms though.
How will the PDFs be used? Will printed filled form responses be (semi)automatically scanned by some OMR software (like https://en.wikipedia.org/wiki/Optical_mark_recognition#Open_source_OMR_software ) or manually read and entered into some recieving openEHR system?