Hi Geron,
I have been racking my elderly brain to recall where I have read your story before "GayAuthor"s and I am sure that I did not read it on this site.. My best bet is "FictionPress" as I have heard from authors on that site complain that their stories have been stolen and placed on other sites under a different name.
There is an author who goes by the name of David Clarke on "Awesome Dude" who has written a two part story called "The Nexus". It is a good read and along the lines of your story. I don't think he copied you but the idea of doors leading to different time/space is similar. As for the plot it is completely different.
See ya and thank you for responding to my comment. I am happy that your are going to share Ch 3 with your fans.
Regards,
Phillip