Hi. We tried moving from V6 to V7 and failed. In end we had to do fresh install and manually pass all transactions for year within short time.
Now we are trying to move to V10 and are stuck at npm. I am just going to install fresh instance and close by FY at 31 Dec 2017 in the old one if the V7 backup files don’t get integrated with V10.
Wishing you all the best in your quest of leaping from V4 to V10. All I can say that it may not be possible due to huge change in DB.