I've created this PHP front end to callflow.
It depends on the filename quoting and current working directory changes in https://sourceforge.net/p/callflow/bugs/11/#d64b.
It's usable as in include with a CSS wrapper, or standalone. There is a sentinal constant to control whether the script can still be run directly when being included in a wrapper.
OK to close this, I just wanted to share in case it was useful to anyone else. I might start a separate sourceforge project if there's enough interest.
Found some issues related to using a pre-defined custom order file, and copying a backup of an order file to final result directory. The former is confusing to the end user when their capture contains more nodes than the pre-defined custom order, and the later prevents the "Default" option from replacing the backed up version on subsequent re-flows if desired.
I plan to rework this, in the meantime in order for the default order file option to override any previously saved order including any pre-defined custom order, create an empty order file and set this as the default.
At CLI:
$ touch empty.orderIn callflow.php around line 60 after
// Provide a system default node order filechange
$orderFile='';to
$orderFile="$scriptDir/empty.order";