Panel Specification

To whom it may concern,

I am looking to make a panel of 3 different designs on one board. I have attached an image of my panel, and I'm unsure of what layers to put my V-cut lines on.

I am using Fusion 360 electronics for my design, and for some reason I can't get my layer20 (dimension) layer to work, and I've tried everything.

In this image, the green lines are my outline layer for my boards. I have also put my VCut lines in my document layer (layer d2) on Fusion.

I think I have successfully used my panlise.ulp function so my nets/names/values are ok for panelisation

Is this ok to submit as a Gerber file?

If it is not, what layers should I use to specify my V-cuts?

Also, there is a large gap in the middle of my panel. Do I need to have anything specifying this is a blank space (maybe a milling layer?)

Looking forward to your response,

Regards,

Alec