I found the problem, i need another GSDML file for the R30IB PLUS controller.
it has to be "GSDML-V2.33-Fanuc-A05B2600R834V910-20170720.xml"
the not-plus version is V2.3 instead while the plus version is V2.33
now it works perfect!
DVD delivered with robot was wrong, it was for the R30ib