I'm having trouble getting a solder mask opening on my testpoints. I have defined the testpoints to have a 65 pad on the solder mask layer. I've also tried assigning testpoints to the top layer and solder mask layer of the CAM output (but I do NOT assign vias). But there is still no opening in the solder mask. The vias I am using for testpoints have the testpoint selection box checked. What am I doing wrong? Do I also need to assign vias to the soldermask layer, even though I DON'T want non-testpoint vias unmasked?