I found a possible glitch with the polyline Add function that may need to be reported. When creating a short polyline, and using DX to specify a length, the first point on the line will disappear and the DX line will not be drawn if zoomed out far. It seems that if you're creating a line that's shorter than what can be displayed at the current zoom level, then it won't be drawn.
I was using a sheet size of 48"x96" and zoomed out to where I could see a couple hundred inches on either side of the sheet because I have many vectors and shapes of my design that I work with outside of the model area. I was attempting to create a specific shape with the first part being a .375" line along the X axis. I tried to draw a polyline by clicking once for the first point of the line, then typing .375 into DX to create a 3/8" long line, but the first point I had clicked would disappear and the DX line would not be created, so I couldn't continue entering the rest of the points of the shape. When I try the same thing after zooming in, it works as expected but I'm constantly having to adjust the zoom level as I enter points depending on the length of the segment.
If you draw a small line, and then keep zooming out, eventually the line can no longer be displayed on the screen presumably because it becomes smaller than a pixel width. I understand that, but the line is still there when you zoom back in, so I would think that the create polyline feature should actually create the line even though you may be zoomed out too far to see it. Perhaps this is a built-in safety to prevent people from accidentally creating vectors that are too small to find, but if that's the case, a message would be nice letting me know "vector not created, too small for current zoom level" or something like that so I don't go crazy trying to find out why the software isn't doing what I'm telling it.
As a side question, does anyone know how to shortcut the add button? Very frequently I want to start a polyline at 0,0 on my sheet and found the easiest way to do it is to click the polyline tool, then go to Tool Settings and just hit Add. I'd like a way to hotkey the Add button for this purpose to minimize trips to the Tool Settings pane. If anyone knows how to do this please let me know!