Board Thread:Bug Reports/@comment-25370207-20140912201111/@comment-4842859-20140912204220

The welding issue is known. The issue being unable to see parts of the sickle is actually a csg error, not a welding issue.

As far as pushing/crashing, I cannot replicate either of these issues. I'll need solid repro steps to find the issue, but it sounds like it falls under that category of "Roblox physics bug, nothing I can do".