I've only just now gotten around to posting about these, but I've noticed a couple of problems since the launch of this product. I have the latest version and am operating on P3D v3.
First, the Fix page does not allow you to plug in an airport. It seems to only take waypoints or navaids.
Second, the +/- key does not function. So if I wanted to create a fix for crossing restriction purposes say 30nm my side of KMSP airport, I cannot do that. In the actual aircraft, that can be accomplished one of two ways. First, you can put into the legs page KMSP/-30 *LSK L1, EXEC*. The second way is to plug KMSP into the Fix page and create a 30nm range ring around it. After doing so, if you hit LSK 1L and plug what it puts in your scratchpad into the legs page, it will create that fix. With the latest update, doing that will create KMSP/30. The problem with that is that is 30nm on the other side of the airport which doesn't do you any good. The second method is handy if you you were on a route like KMSP WLSTN7 GRB KGRB and you have not been cleared direct the KGRB airport yet, but you still need to create a crossing restriction. You can't just make one from the GRB VOR because it's not located on the airport. So you can use that second method from the fix page to plug in before the GRB VOR and it should create a fix along your current route of flight that is still 30nm from the KGRB airport. That function doesn't seem to work either.