We can migrate your data to OpenERP v6 using the only free Migration module
for OpenERP, at the fraction of price. We can migrate your data not not only from "official" modules, but any OpenERP module, whether it is certified, official, extra, or any third party. We can even do migration of v4 to v6, in this case it would be a tedious process, still doable. it could be 5->5 or 6->6 version, as well, of course it is in case you want to do a cleanup, by not moving all the data.
We are doing already second migration wave (4->5->6), so the Migration Module is stable and mature. And if you feel like you want to do it yourself, you are welcome, it is freely available, we do not charge money for the instrument, it is GPL, unlike those scripts, by a publisher.
We charge money if you want pre-configured mappings for your particular setup, service or consulting.