I'm trying to have a copper polygon without solder mask, so I copy the polygon from the Top layer to the Top Mask layer. When I generate the Gerber files, the Top Mask layer only contains the original contents (pads). I've tried putting in this layer lines, texts, pours and so on, but they never appear in the Top Mask gerber file.
¿Is it a bug, or I'm missing something?. I've googled, some say they got it (but don't tell how) and others say that you must use tricks. I've tried these, including an auxiliary layer, to no avail.
Thank you.