delft3dfm_202x.0x_lnx64_sif0x.tar.gz:
0. Download and install Singularity: https://sylabs.io/guides/3.0/user-guide/installation.html
1. Unpack the Singularity sif file with the runscripts. Keep them together in a separate directory.
2. From within your working directory: execute the relevant run_script next to the sif file. An example script for this, run_singularity.sh, is available.