Thanks everyone for the replies so far.
To be a bit more specific, I need to create new entries in my custom object when creating a goods receipt in MIGO. For this I'm using MB_DOCUMENT_BADI, and I'm trying both methods MB_DOCUMENT_BEFORE_UPDATE (before the commit) and MB_DOCUMENT_UPDATE (after the commit).
I tried firstly using transaction manager and it short dumps because commits are not allowed in either of these methods. Then I tried the slave transaction manager (steps 1, 2 and 4, as described here) but also failed.
Thanks and regards,
Custodio