How to input covariate of continuous behavioral ratings during an experiment?

Hi,
I have continuous behavioral ratings that correspond to specific time points of my fMRI stimuli. I would like to look at differences in functional connectivity in relation to these behavioral ratings.  I was trying to input the rating as a 2nd level covariate in the setup tab using the "import new covariate data from file", but I'm not sure what the format that the data should be in. Right now I have a 2 dimensional matrix of time by rating (these ratings would be the same for all subjects), but the covariates that already exist from the preprocessing are only 1 dimensional with a single value for each subject. Therefore my questions are:

1. Is this the right place for me to import a continuous/temporal behavioral correlate?
2. Do I need to add a 3rd dimension for participant and is it possible to import a 3 dimensional matrix (sub x time x rating) as a covariate?
3. Alternatively, would I need to condense the time and rating into a single dimension that contains ratings that correspond with the sampling rate as the fMRI data?

I apologize in advance if there's something obvious I missed about this in the tutorials/forums and such!

Thank you!
~Em