This web site is Apple Safari allergic. I tried to send a support request to you from my iPad using Apple Safari. It took me three tries to actually get logged on. Then I spent the time to type out the message, clicked on submit, and.... Nothing happened. It just sat there. So I copied the message to my Mac and am going to try again. It took me several tries to actually log in using Safari on the Mac.
Note that I have no issue logging into the site using FireFox. In my experience, this generally indicates that the site is using some Microsoft "enhanced" product rather then following standard HTML protocol. If this is correct, that might be where you need to look to resolve MacOS login issues. I tried, just to see if this would resolve the login issue.
Also, I should point out, on the iPad when I tried to submit a help request, it asked for my license number or key or whatever. I don't think I ever have received a key or license from any App that I have purchased from the Apple store. As a matter of fact, SkySafari Pro on my Mac doesn't have one either. I know you need to be generic, but the site could use some intelligent parameters that ask where it was purchased and go with that or alternatively, the link from the app to the community could automatically provide this data and login information to the forum site.
Side note. I was willing to help with you beta testing, but I gave up trying to submit information because this site it so very difficult to actually log into. I have done a lot of beta testing with a number of different companies and I have never run into such difficulties trying to help.