You can download a midi song file you like the style of, open it in RB that will split to separate tracks and detect the chords then you can use sections by copy n paste or whole tracks to make up your own UT that will play in a different key/progression.
You can change the key of the midi then save the wav file to another template for the UT instrument that will go in the same folder and this will give you UT a lot more variation.
You can change the tempo of the midi and save as the same instrument but with a tempo of 140 instead of 110 giving the UT a wider range of usability.

Just try it with a midi file, make sure you have a 2 bar count-in by inserting or deleting bars, and have Bar offset set to -2
Export the midi track to wav, drag the wav into RB on a blank track below the midi tracks so it is lined up with 2 bar count-in,
File > Save As > File Type (.?G?) SGU, Create Folder for UT with tempo "Guitar, Acoustic, Rhythm, Slow Country Sw65"
Open that folder save filename eg: Guitar, Acoustic, Rhythm, Slow Country Sw65 song 01.SGU
Choose the wav file track as Audio.
Delete the wav file track and change the key of the midi
Now wav export and drag in as before
File > Save As > as before but as song 02 template Guitar, Acoustic, Rhythm, Slow Country Sw65 song 02.SGU
and so on in different keys.

Now you should have a UT to try, if it sounds good you can make some Endings template for it quite easily also.