SamyGO

First...
Could you check, do you have access to u-boot by holding "~" on TV boot ?
I`m asking because it can be deleted by samsungs latest firmware and then no chance for you to boot from USB. I checked another, LNxxB650 TV (hardware is same as yours), and i found empty(deleted) u-boot and other partitions. I think it is because of samsung firmware.
If you need boot from usb, you need to restore bml0/2 first. You can`t do it without telnet or console over exlink. You can`t run telnet enabler from content library too. Log you attached seems to be good, i mean, you get good signal from TV.

Only one way i see in this situation- if you have once more firmware to upgrade TV and TV accepts it (do not upgrade, just check it), then you could flash required partitions to TV over normal TV upgrade procedure, but not with firmware files on USB. Here is an example what i suggest you.(read from "Some Experience")
Or if you do not have any firmware TV accepts, you could activate alternative firmware, and then TV should accept firmware upgrade to the same, 1018.1 firmware, right?

Really bad.

Can you check how are channel settings exported to USB - in one file as archive or separate files? Read here
If you get files as in example on wiki, then i have no idea how to help you... But if you get files as archive (like on C series TV), then might we could import partition switch flag to boot TV to alternative firmware. Did you upgrade TV once? or you have bought it with 1018.1 on board and you do not know is here any alternative firmware or not?

p.s. Are you sure your firmware is T-CHEAUSC-1018.1 ? I found only 1012.3 on samsung download site. Where did you get 1018.1 from? OTA?

The link i gave you is "how to export channel list", but not how to activate alternative firmware

If you can, please try export list to ext3 formatted USB, but if you get error, fat32 should be ok then.
I do not think you get u-boot promt. But who knows...

No, you have debug ON - you have log from TV and magic button does not help.

So instructions are:

on PC:
1.download this archive.
2. Extract archive and edit install.cmd (change A: to letter of your USB dongle, be carefull, if you make mistake, it formats your C drive )
3. run install.cmd

on TV:
4. TV is off
5. Attach USB (it is ext3 after, you cant open it under windows) to TV
6. Power TV on
7. Activate CHannel import/export by pressing shortly VOL+ and after ENTER for 10 secs. Import settings from USB to TV
8. Go over menu to Alternative firmware and activate it.

Steps 4-8 are similar to this manual step1

Here is step7.

When the TV is switched ON press Volume Down once and then press the Enter ? button for 10 seconds.
This will display the "Channel Import / Export" Menu.



Choose USB to TV for channeldata import or TV to USB for copying the channeldata to the USB drive.

If this doesn't work, check that "Speaker Select" in "Sound Menu" is set to "TV Speaker". Anynet+ (HDMI-CEC) should be disabled.

You are doing something wrong...