w00000t... switching finally working nicely for me on all my rigs, I just needed to adjust gpu-engine settings for each pool to avoid sick gpus.
How did you manage to do it? I use miner from nicehash v5 and example conf file from
https://nicehash.com/multialgo/ but when run it I always go to backup pool 3333...
This is what I get:

Sorry I'm just seeing this now, I didnt realize you had quoted my post with a question
The example conf should work OK, but it might still need you to make some edits.
For example, if you are using windows, you have to remove gpu-threads from the pool profiles and use it only in the core config. Also, to really get this working right and stable, it helps to know your GPUs default clock speeds for engine and memory.
What OS are you using? What did you set for your worker password on your machine? I started using the f0=xxx;f2=xxx;f3=xxx etc where xxx represents the speed in MH/s for that algorithm. that helps the pool decide which one you would profit from the best automatically and set the other pools to dead. that *might* be going on with your config if you just are using pass=x
also, in your image, you have 'backupool' defined and that is just there as an example for you to use an alternate site as a backup pool.. its not a real site.