To improve the tests that reject montages that are not applicable, it would help me a lot to know what is the list of channels in your recordings and in your montages.
Please .zip together the channel.mat of your recordings and the montage_*.mat file you can't use (in the montage editor with the button ALL selected, click on the montage, then on the save button - change the file format to "brainstorm .mat"). Upload this file somewhere and copy the download link here.
Thanks