Not able to administer deployment

hi all,

I’ve just installed VW and am struggling to get it working.
It seems that you cannot do anything without using SSL, so i’ve installed nginx and am using that.
I’ve read up and apparently i need to add an environment variable with a token in and that should enable the /admin page.
But when I go to the that address, I just get a error 502 bad gateway.

Also when i try to import my google chrome password file it gives me an error which weirdly includes the html code of the error 502 bad gateway page.
so something is definitely up here. as another point, I don’t know if it is by design or not, but if i do anything so much as refresh a page in the gui, I have to re-enter my master password again (given that its so long, its a bit of a pain)

details
running in a docker container. bridge mode. exposing it as port 8015 (80 is already in use for other things)
nginx is set up to proxy it on ssl using port 9999 (443 is already in use for other things)

note that this is the first time installing both nginx (actually swag) and, obviously vaultwarden too.

can anyone offer a solution or some pointers please?

ok i worked it out as being some weirdness in my reverse proxy setup.