Hi.
The first problem is related to transformations -objects are grouped and the group was transformed. By selecting the objects and ungrouping you can remove the unwanted transformation, unnecessary clipping and grouping.
Select all (Ctrl+A) and ungroup objects a few times (Ctrl+Shift+G).
The latter one looks interesting, have to look deeper what causes the problem.
However if you want a solution, just select the bottom-most line, copy it (Ctrl+C),
select the problematic curve above and paste style (Ctrl+Shift+V).
Edit: by opening the xml editor (Shift+Ctrl+X), looking at that object's style attributes, there is
vector-effect:non-scaling-stroke
-which causes the "unexpected" behave. If you remove that part it gets back to normal.