You would be wise to take 1 scanner at a time, as the TRX1 and the SDS use completely different concepts to store and manage their data.
Each of the articles has a 'Nuts and Bolts' section to help with some of the terminology. Read these first.
Let's start with the TRX-1
wiki.radioreference.com
At the bottom of this you will find a section called 'Additional Resources'. Here you will find links to the Easier to Read manual for the TRX-1 (and it's associated programming software) along with several videos to help you along
Now onto the SDS scanner
wiki.radioreference.com
This is a 2 page document. On the first page, concentrate on the 'Relevant Resource Material' section where the Easier to Read manuals for the SDS and Sentinel (Uniden's programming software) can be found. Pay attention to the 'What Must I do first?' section. Now on page 2
wiki.radioreference.com
You will see a whole section devoted to various videos.
As you found out pre-programming isn't always the best way to go. As an alternative go to the Texas forum and ask for programming files (EZ-Scan for the TRX-1, Sentinel for the SDS - they are NOT idnterchangeable!)
It's a lot to grasp as a newcomer. As it was said in the 'Contact' movie with Jodie Foster, 'Small Steps, Sparks'.....Mike