The uRemote need some time to read content form the drive. As that is only USB2 connection it take some time. You can move your subfolder inside of the MultiTrack folder in this case the uRemote and the uTrack-X32 will still able to open those files.
We do not support to reduce the channel count as the uTrack-X32 can be used with no uRemote as well in this case the card lack of UI then the user have no feedback if previously reduced the channel count then the card does not record all of the channels.
The consol handle the routing in 8 channels groups we cannot change that as this depend on the console firmware.
The reason why your setting does not applied in the recording because in the routing/card output you selected the the inputs as 1-8; 9-16; 17-24; 25-32 psychical inputs to the card then in the channel configuration you just able to select which fader handle the selected psychical inputs, but that does not have impact on the card input routing.
Does that answer your question?