Blurring the edges of masks in Vegas?

[Chaobunny12]

Well I just downloaded the free trial of Vegas pro to decide whether I'm going to get it, and I'm playing around with one of my project files to figure out how the masking works. Granted, I know I'm not going to get it in one day, but I just have a general question.

I'm masking a face over another character's face for a "memory" like effect (the too characters have similar faces, one is a reincarnation of the other. It's Eruruu and Mikoto from Utawarerumono, if anyone knows the series.) I gradient mapped the masked face to have the same tones as the original scene. But even though the two characters are similar in appearance they have different shaped animal ears, and I want to blur the edge of the mask to blend it a little better. But when I feather the mask I get a blurred black border, which I presume is from the black area of the clip around the mask, but it does not good in trying to blend the two scenes together. Is there a way to prevent this black border and still blur the edge of the mask?

[AaronAMV]

Feather in the mask on top layer, and add a blur to the bottom layer?

[Kanti13]

I presume is from the black area of the clip around the mask, but it does not good in trying to blend the two scenes together. Is there a way to prevent this black border and still blur the edge of the mask?

Is the feather type set to in? If there is a black area around the mask than an 'out' or 'both' type feather will include that space, but an 'in' feather shouldn't.

[Chaobunny12]

It does it no matter whether I set the feather type to in, out, or both.

[JaddziaDax]

screencap pls?

and it sounds like you cut out the face of the character you wanted to remove leaving a big black hole then tried to place the other character in the mask? or am i wrong?