Hi Anis - was this something that you modeled in MoI, or was it some imported geometry?

Somewhere along the line some of the edges in the bottom area of your model got split into 2 edges rather than one long single edge:



It is those split edges that seem to be difficult for Shell or Offset to handle, which seems to be a bug. But if you had long single edges there instead of ones split into several fragmented edges, it would work.

I'll see about adding in a "Merge" utility function for the next v2 beta for gluing fragmented edges like this into longer single edges, that will be useful for repairing stuff like this.

- Michael