All Humax recordings on the 2000T are encrypted. First, can I suggest you read
Things Every HD-FOX T2/HDR-FOX T2 Owner Should Know as the majority of the information there applies to 2000T as well - especially point 5 - encrypted recordings.
You say you've ftpd the recordings to your PC. All is not lost, but you
will have to transfer files around to sort the problem out. At this stage you have
not lost the recordings. There is just no way to view the content on any computer in the way you have transferred it. Which files have you transferred? .ts only or .ts, .nts and .hmt? If the ts/nts/hmt then the solution is easier. Your easiest - but time consuming - solution would be to copy some of the files (a.ts, a.nts, a.hmt - where "a" is of the form "The Long Arm_20181110_1723") from the PC to a USB device. Disconnect and insert into Humax and use the Humax move/copy command to move the files from the USB device to the Humax hard drive. This should decrypt StdDef files. You could then re ftp them back to the PC and they should be watchable.
Alternatively, you could ftp the files back to the Humax and then save to USB (connected to Humax) or decrypt the content using the DLNA method.
If you only have the .ts file, things are going to be difficult. You need valid .nts (maybe) and .hmt (certainly!) files for the previous method to work.
I think the following will work. You could copy an existing [still encrypted] StdDef .hmt/.nts file to your PC, rename them to match a .ts file on your PC that you wish to decrypt and use the set of files as above. I would need to check this to be sure - and can't at the moment. If it doesn't work, you may need to patch the .hmt file. Oops. It's not that easy!