Thanks, You confirmed my reasoning. I used 127.0.0.1#5335 precisely because in my setup containers communication is based on host system - I've not created a dedicated network.
Probably macvlan or ipvlan would have been a better solution, but I wanted to keep it simple.
The pasta is still quite mysterious to me though. That addressing for --map-guest-addr and for --dns-forward that I showed as process parameters is the default - I didn't set that IPs in any way.
So far everything works well, but I wonder if I should not use these addresses for communication somehow...
Pasta is a fairly new stack, so I think more users may be interested in this type of setup.
Let's leave this thread open for a while, perhaps someone will add some interesting observations.