Working off of my last question, I can access my server's FTP over the LAN but not over the internet. I'm using Filezilla on port 666. My router/modem configuration is as such (similar to other post):

1) Modem connects to WAN
2) WAN port on modem connects to LAN port on Router
3) Modem internal IP address is 192.168.0.254
4) Router internal IP address is 192.168.0.1
5) Modem has DHCP turned OFF
6) Router has DHCP turned ON
7) Router is running Tomato firmware and it's set as 'Router' (not 'Gateway')
8) The internet is working (just had to say that)

I've set up port forwarding both on the modem and router - both route port 666 to the IP address of 192.168.0.3 (TCP); that is the IP address of the server which has FileZilla running. I don't know if that's hindering anything but I've also tried it with just the modem and just the router...same result. I've also tried setting the server to be DMZ (both on router and modem).

Neither router nor modem have anything in their logs about denying inbound traffic on port 666 so my ability to troubleshoot stops there. I've tried contacting my ISP (Telus, running on mobility plan...it's a "Smart" Hub) but they weren't much help. They said they only block port 25 and 80 and maybe a few others, but not most ports. I test whether or not the port is open by going to canyouseeme.org - I don't know whether or not that would produce a 'connection refused' result just based on the fact that the FTP requires a login...I'm not well versed on this matter.

FWIW, sometimes I get a 'connection refused' error on canyouseeme.org but mostly it's 'connection timed out'.

I don't know what else to do at this point.