When trying that, I get a different error (see attached). I got the same error when trying
-model 'cToM_Negative_A+(1|Subj)'
I also tried
-model 'cToM_Negative_A+(0+relationship|Subj)'
and got the "model test failed" like before. Finally, at my colleague's (Dustin Moraczewski) suggestion, I tried removing all doubles in Subj and running
-model 'cToM_Negative_A+(1|Subj)' \
to test the most basic usage, and it still failed. I then tried running MEMA instead with the same covariate (cToM_Negative_A), and it worked, so I don't think it's a problem with my imaging data.