The arranger is an awesome tool to play live.
Don´t think on it as the Ableton Live arranger where you basically use it to define a structure.
The OT arranger is more like “scenes” on ableton Live, you can create loops, jumps, offsets, mutes, etc.
You can create rows to set a suggested pattern order but then you can choose when to jump to a particular row.
Also you can leave and back from/to the arranger seamlessly.
You can define which OT Scenes will be selected for a particular row.
You can use REM rows to have labels so you´ll know what is what, useful if you need to learn a lot of patterns, relations, sequences etc.
The offset can be very useful.
You can use the Offset parameter to convert 1 pattern into several virtual patterns, this is useful specially if you use loops.
Lets say you have 2 samples of 4 bars each that represents part A and B for a song.
You can use a single pattern to hold both of them on a single track and then use the arranger to choose which one will play and when.
The key is make an 8 bar pattern then put sample A on the first half and sample B on the second. Then on the arranger setting an offset of 0 for that row/pattern will play A, and an offset of 64 will play B.
The key for this is to use per track scale and set for the track that will play A and B a Pattern Scale of 64/64 1/2
This will make that track twice it size but you won´t get extra steps, there always will be 64 steps max, so to achieve that, the steps for that track will run at half the speed. That means you loose resolution but that doesn’t matter for this track. This track only needs a single trigger on the very beginning to trigger a sample.
So render A and B to a single Wave, so bar 1-4 is A and 5-8 is B, then create on the OT a 2 slices sample.
Place a trigger on step 1 playing slice 1, and 1 trigger on step 33 playing slice 2. Because it speed is the half, Step 33 correspond to step 65 at normal speed.
If you press play now you will see that for that track the step will reach step 32 and then will back to the beginning (I asume you have master length to 64).
Now place that pattern on the arranger as a row with a length of 64 (and 64 repetitions to keep it playing)
Pressing play now will play A
Now in the arranger duplicate that row but now set an offset of 64
If you press play now being on that row, all tracks will play starting from step 65. The other tracks will play step 1 because there is no step 65, but for the track that holds A and B there is Step 65, in matter of fact it is the step “33” the one that holds B. So You will listen to B variation of this loop
Having this two rows on the arranger allows you yo jump from one to another whenever you want, so this way the arranger works as a helper and not as a structure ruler.
Note that you can set a Scale of 1/8, this mean you can hold 8 sample variations per pattern, or even more using other tricks, like offseting to a part that hasn’t any trigger for that track will keep playing the last triggered slice.
Using this technique you can have full backing sons divided in “moments” and use the arranger to play them automatically or manually.
Hope you get some ideas from here, there are many things to write and very short time, sorry.