I just downloaded and uploaded DtRegister 3.1.1a on my joomla 3.4.1 site, but now I would like to migrate the data from my old joomla 2.5.28 with DtRegister 2.8.8f on there.
This is quite the task and would very much like assistance as it is also an urgent one.
The instructions you need are in the package readme file. First uninstall DT Register from the Joomla 3 site and DROP all _dtregister database tables from the J3 database. Then you'll need to upgrade DT Register on the Joomla 2.5 site to the current version for that series of Joomla, which is 2.8.14. Then follow the instructions in the package to migrate your data. The order of things is important.
Nathan is no longer affiliated with DTH since the recent acquisition. You can connect with him and get any type of Joomla website help at
www.JoomlaEmployee.com
.