Here is BatchFormatConversion 1.2.1. It works fine except the sample format parameter, which is ignored. In this version each output file is written with the sample format of its corresponding input image. This is due to a bug in the PI Core application (see the comment at line 225 of the script). I have identified this bug and will fix it in the next version. Despite this bug the script is perfectly usable for DSLR_RAW to FITS conversion, since for this task we don't have to change the original 16-bit integer format.
For completeness, I have added also an output hints field. Let me know if this version of the script works as expected.