I'm a new user of Anime Studio and I'm loving it so far! However I have come across a problem and I'm sure it must be a common one but I've searched and I can't find any solutions.
Basically I have my eye mask setup and it all looks fine in the workspace:
But when I render it out with antialiasing there is a visible outline around the mask shape:
I just had the same problem. There's nothing you can do about it as it is (arguably) a bug. You could try duplicating the mask shape and making the new shape slightly bigger so it covers the lines.
I thought that might be the case. Interesting idea bout the duplicate mask shape, I'll have to try that one, but for now I'm just going to avoid making my character blink
You can make the horizontal line above the eye invisible by selecting it with the Hide edge icon in the fill section of the tool palette. I hope that solves the problem.