Fixelcfestats: one-sample ttest using random sign-flipping

Dear MRtrix3 experts,
I would like to use fixelcfestats to perform a one-sample ttest. I have searched for the related topics but still have two concerns:

  1. Creating the correct contrast matrix and design matrix file
  2. Using the right options
    I used single column of ones in the design matrix and single 1 in the first and -1 in the second row of contrast matrix for negative and positive effect. Fixelcfestats can recognize them and run without errors , but I do not know whether it is correct or not.
    For the options, I only used the option -errors ise, is the exchange_whole option also necessary ? In the thread , @rsmith referred to the -exchange_whole option when sign-flipping was used. I tried to read the Winkler et al.,2014 paper about the restricted exchangeability, but still do not know how to create the exchange_whole file for one-sample ttest. Could you give some suggestions ?

Thanks in advance !!

Best wishes,