kcp over udp2raw does not work well

[linnuxx]

English Only.
kcptube:
mode=client
kcp=regular4
inbound_bandwidth=500M
outbound_bandwidth=50M
#kcptube should listen on 51820, so the wireguard client can connect to this port.
listen_port=51820

#this is the port of server side's kcptube
destination_port=5900
destination_address=0.0.0.0
encryption_password=qwerty1234
encryption_algorithm=AES-GCM

mode=server
kcp=regular4
inbound_bandwidth=1G
outbound_bandwidth=1G
#Listening on 59000
listen_port=5900

#The port number of server side's wireguard
destination_port=51820

#if wireguard and kcptube are running on the same server, use localhost, or 127.0.0.1, or ::1
destination_address=localhost
encryption_password=qwerty1234
encryption_algorithm=AES-GCM

udp2raw:
./udp2raw_amd64 -c -l0.0.0.0:5900 -ripvps:443 -k "passwd" --raw-mode easy-faketcp --seq-mode 0 --cipher-mode none
./udp2raw -s -l0.0.0.0:443 -r 0.0.0.0:5900 -a -k passwd --raw-mode faketcp --seq-mode 0 --cipher-mode none

the command does not want to run.

[wangyu-]

I suggest:

1. use faketcp instead of "easy-faketcp" since the latter is known to have worse compatiblity (and you will need add iptables either by -a or manually)
2. look at udp2raw log and see what it says