Group level reports are missing

[hechlera]

Hi,

following the implementation of fmriprep in our lab, I am now working on a container for task analysis. To practise, I started with this one - it works fine for the first level analysis, but when I run the group level, I am missing the group level reports (html) that FSL should technically create.
For the first level analysis, I found them in the working directory but none occur in the second level. I do get the (I assume correct) output in the derivatives folder (grp_all) with the following files:

sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_desc-3cond_nlocalmax.json
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_desc-3cond_nlocalmax.txt
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_desc-3cond_plocalmax.json
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_desc-3cond_plocalmax.txt
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_desc-clust_zstat.json
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_desc-clust_zstat.nii.gz
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_desc-fwe_zstat.json
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_desc-fwe_zstat.nii.gz
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_nclusterindex.json
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_nclusterindex.nii.gz
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_pclusterindex.json
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_pclusterindex.nii.gz
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_zstat.json
sub-p888_task-3cond_space-MNI152NLin2009cAsym_desc-preproc_zstat.nii.gz

I might have something backwards here with the way FSL FEAT works (I used SPM beforehand). In the first level, I specified three contrasts that are correctly reflected in the report.html. I'd be glad for any help understanding how I can recover/create the higher level reports or in understanding where I maybe went wrong.

Best regards,

André