@Emma_Kassy/ @Calle_Hedberg - would you please advise on this use case, please? @damasceno.lopes - kindly share your logs with us too since we can not tell much from this information, thank you.
I have not been able to use the GML import on 2.29, it always bombs out with a nullexception error.
yesterday, in order to import a large GML file with updated orgunit coordinates, I had to upgrade a copy to 2.30, import the GML data, export the organisationunit meta-data to xml, and then import that into the 2.29 instance.
My feeling is that such bastardized procedures should NOT be regarded as a “solution” - it’s more like a really time-consuming and cumbersome work-around because the developers do not have capacity to deal with all bugs (2.29 is by now basically no longer supported, so I doubt that bug will ever be fixed).