THANK YOU!! THANK YOU!! THANK YOU, DOK!!!
I finally got FTP working for both, the D8B and the HDR as well. YAY!!! This never really worked for me.
I'm technically not new to FTP, use it regularly for work, but somehow never got it to work for the D8B or HDR... and thanks to Dok's mention of suggested IP range assignments (i.e. reserved ranges for DHCP, Servers and Printers etc.), I finally noticed what I did wrong!
My DHCP assigns IPs ending in 100-199... but I didn't realize until just now, that I can limit this, and that it was limited to this range of 100 IPs out of the box, for the DHCP.
I didn't even realize I can use IPs below that, and like an idiot, always thought "wow - I have a lot of IPs in use, already... better pick one that is higher than what's actively assigned by my DHCP, already" and entered something like "192.168.0.180" or so for the D8B or HDR... not realizing that this would STILL conflict with the DHCP.
I only noticed that nothing got assigned to the lower IPs from 2-99, when I checked my DHCP client list (nothing with an IP under 100), and then looked for a setting where I can define what IP range the DHCP should supply, and found that it was already limited to 100-199.
Without the Dok's guide, I don't think I'd have ever looked for this. So, thanks AGAIN!!!
When I FINALLY tried a lower IP for the first time, Cyberduck (that's what I use for work), STILL wouldn't work and gave a "550 File Not Found" error, even though all the other settings looked right.. after some trying around, I just figured I'd try with FileZilla.
FileZilla worked IMMEDIATELY for me... just with a different IP in a lower range than I had previously tried. Now the connection is practically instant. Happy times, YAY!!
Just sharing all of this, in case there's someone else out there, who is stuck with trying to integrate the D8B and HDR on an existing network (and not change connections to use a twisted pair cable, every time you want to transfer files), while failing to see that you can limit the address range served by the DHCP, and that it should work if using an IP outside of that range.
Also... Cyberduck didn't work for me, but I'm not sure why.
Do I get an FTP operators certificate now, or something?
There can't be THAT much left to learn to get my MCSE, right?