Migrating From Rebranded Cs-Cart To Cs-Cart


I have a rebraned CS-Cart package (iVendi) and would like to know how much work it would be to migrate the date to an original CSC licensed install?

I started using their webshop at v1, then had to do a complete reinstall for v2, then again to v4. Kind of getting tired of redoing the entire site ever other year. My current version (4.0?) has some bugs, I can't update anything but keep getting annoying pop-ups, extra language installs need a PhD in SQL/PHP, can't edit orders anymore etc etc… I don't want to keep spending money and time on this thing.

Any advice would be greatly appreciated.