Problems with Vignette color palette settings not sticking

I don't know if this is a problem or by design.  My default color palette is CMYK.  When I open the Vignette Effect (both in Draw and Paint) the color palette comes up as RGB.  I change it to CMYK, adjust my vignette settings and close out of the dialogue.  If I decide to change those settings and open Vignette on that same image, the existing Vignette settings do not come up.  Rather, it reverts back to RGB and I have to change to CMYK and choose my correct color all over again.

What is worse is that I can't even tab between the C, M, Y and K to fill in my values.  I have to click in each one with my mouse and type the changes in.  Normally, in other areas of the program when working with palette colors, I can tab between those values, and when I am done, I can hit "Enter" to complete.  Inside Vignette, I cannot hit enter to complete.  The only way to get out of the Palette dialogue box is to click the mouse back into one of the values.  Then the preview will update with those settings and I can click on the "x" to close the color Palette closes and "OK" to finish Vignette.

This is a tedious process and seems to me like it is not behaving correctly.  Has anyone else experienced this and if so, did you find a way to fix it?