Validation Errors While Saving Record(s) : LoadData

I'm currently implementing the creation of test-data through the loading of csv-data

For 1 object I do 3 test-loads :
- load A
- load B
- load C

I need to do this because there are several relations between the objects.

If I do the 3 loads I get the error : Validation Errors While Saving Record(s)
But it doesn't give me any details what may be causing this

But the strange thing is the following scenario do work :
- load A, load B
- load A, load C

Also running these tests take a lot of time..

I get more and more the impression that loading data from csv is not really an option, if you have many relations between objects