(video tool version could be obsolete)
This is an alternative for php script converter for convertion/migration

Here a database with a bit of information, running on a virtual machine
A bit slow on virtual machine but after tests could convert larger amounts with same memory amount

Also for vbulletin, phpbb2,phpbb3 and ipb

Possible php script with same method or other programming/script language

vBulletin to Kunena:

SMF to Kunena: