Hi s7r83dg3, yeah the geometry library that MoI uses does not always handle offsets correctly in joined areas where things don't meet in a 90 degree angle.

If you use Edit > Separate to break your model into individual surfaces, you can kind of see how the offsets don't "naturally" meet up in situations like you have here, for example offsetting each surface individually results in this:



You can see there that in order for these surfaces to match up properly after their offset, there also needs to be some extension happening there as well, including an extension of the unjoined outer edge, which is an area that is not handled by the geometry library currently.

I have heard from the authors of the geometry library that they do plan on improving offset in the future though.

For now if you want to offset things like this you may need to use Edit > Separate to break it into individual surfaces, offset those surfaces, and then use those pieces to build off of to create what you need.

- Michael