Hi there,
I'm experiencing a problem with the latest 
version (v1.2.0) of the 'File' (dropdown select) extension - listed on 
the store here: https://www.seblod.com/store/extensions/602
The 
problem manifests when going into COMPONENTS > SEBLOD 3.X > 
FIELDS.  If I now attempt to open a previously-created item that uses 
the 'File' extension, I'm presented with the following message:
"An error has occurred. 
Call to undefined method JCckDev::getFormFromHelper()"
Likewise,
 if I create a new item of the 'File' type, selecting that type from the
 Type dropdown does not update the page/form properly - the upper fields
 remain intact, but the lower section (which would reveal additional 
fields specific to that type) does not load, and instead shows the 
message "Oops! Try to close the page & re-open it properly.".  Switching to any other Type seems to work as expected.
The
 only fix I've found has been to revert to v1.1.1 of the extension.  
This is fine for now, though Joomla continues to prompt users to upgrade
 to v1.2.0 of the extension, and I'm not sure what v1.2.0 is intended to
 fix.
Thanks in advance for any consideration - and for a generally excellent application.