The process is described in the programmer's guide:
The (sometimes) hard part of adding new matrices is obtaining metadata for each new matrix, and transforming it into the DataTable. We would be delighted to add new matrices to the package. Many example scripts for preparing pfms and metadata are included in the package source.
You may also be interested that for the upcoming Bioconductor release, we have added
- JASPAR 2016
- HOCOMOCO 10
- SwissRegulon (hg19:FANTOM5)
We also plan to include pwm similarity measures calculated with TOMTOM, from the Meme suite.
Let us know if we can help.