Don’t know if it’s related or not, I also have a bug relative to color used to draw vector.
Create a vector shape, with line color + fill color.
Select shape
Change fill color
Draw a new shape with border line color defined as color brush.
The color brush is not applied (applied: last color used to fill previous shape)
Change color brush.
Draw a new shape: color is properly used.
Select first shape, change fill color again.
Draw a new shape: last color used to fill previous shape is used instead of color brush
Here an example (sorry for sweet colors 
)
Grum999