OK. I tried CSV import. For 11k records it took 6 hours. I have over 200k to do. I tried Celigo and for some reason it failed. The script is a map-reduced. I'm launching it manually. I did not think about WebService. You think it can do it ?

Do you need support in the Celigo side?

Not yet but I may if cannot fix that issue

Let me know - I can point you in the right direction