Written
There is no automatic upgrade from CFv3 to CFv4. The underlying code is very different and Max has chosen not to write a 'translator'.
You can copy and paste chunks of code - for example the Form HTML and some custom code - but the form functionality, emails, DB Save, etc. has to be re-built. Given a choice I recommend re-building from scratch in CFv4 but I recognize that's not a simple task with 50 forms. If there are groups of similar forms it may well be possible to consolidate them with a little extra code.
