D-Link DIR-810L connect failures

Hi, I'm having problems with 17.01.4 on an D-Link DIR-810L (HW version A1).

I've successfully(?) flashed 17.01.4 after following the instructions on
https://openwrt.org/toh/d-link/dir-810l , I had to take the extra steps to append a signature (command I used: ./ncc_att_hwid -f lede-17.01.4-ramips-mt7620-dir-810l-squashfs-sysupgrade.bin -m "DIR-810L" -H "A1" -r "WW" -c "1.0" -F "1.02B22" -a).

Now my DIR-810L boots LEDE/OpenWRT, and when I NAT the traffic from the WAN interface through my computer and out onto the internet and I tcpdump traffic I see it's requesting and getting a DHCP address from my computer, and it also starts talking to NTP servers (0.lede.ntp.org if I recall correctly) and getting answers, so the NAt in my computer is working.

I have to configure the interface used for the DIR-810L to use VLAN (modprobe --first-time 8021q ; ip link add link eth0 name eth0.2 type vlan id 2) and configure udhcpd to listen to eth0.2, but then the traffic in the previous paragraph wo

So it seems LEDE/OpenWRT does work.

However, I can't reach the router in any way.

It seems all five interfaces on the DIR-810L are one common virtual interface. A
ll use VLAN 2 and none answers on any port (just as if they're all WAN interfaces).

Any ideas?

I've also tried to reach the emergency firmware flashing page as described on LEDE/OpenWRT's DIR-845 page (and on D-Link forums) using a large variety of interfaces (WAN and all LAN), IP addresses ( and on the computer and and as addresses on the router I'm trying to reach) , and seconds-to-hold-the-reset-button but that doesn't work for me (it does work on my DIR-845 though). The DIR-810L never replies to ARP requests when booting to emergency flash mode.

I'm really stuck here and would appreciate any help.