I'm currently using XBench to check the TMs and Olifant to edit them and found out that I can configure Olifant as the TMX editor of Xbench.
From XBench help file: “For example, to configure OKAPI Olifant for segment positioning, you must select there the Olifant executable and specify the following in Command-Line Parameters: $Filename row=$Segment col=trg edit=yes. Other TMX editors might have different values for this field.“
However, every time I have to make an edition a new instance of Olifant is opened, so every time I make an edition I have to save the TM, close Olifant and then open it again for the next edition. I asked the Xbench team and unfortunately they couldn’t help me with this.