Hi James, when you offset with "By distance" mode, there is still a point input that is taken for which side to offset to and if you have multiple shapes and you want to offset inside then since it's a single point it can only be inside one of them.

In the new beta you can use a negative distance and pick a point outside of them all as an alternative. The allowing negative input is new for this last beta release and I can repeat that it seems to interfere with the Trim option, I will investigate that. Before this last beta negative distance was not allowed with offset.

Thanks, - Michael