Ok, I have something going here to load the files in their original format in Renoise:
After installation, this tool adds a 8 bit sample loader > Load IFF or RAW file… menu entry to the Tools menu.
Clicking on it opens a file browser. Selecting an IFF or RAW 8 bit signed mono file will load it in the current instrument’s current sample 
For IFF files: sample rate, loop start info, and sample name are used if present. Octaves and compression are not supported (maybe a nice addition).
For RAW files: a sample rate of 16726 Hz is assumed (allow to customize this would be a nice addition).
Note: this needs more tests at the moment.
If you want to try it you will need the files in their original format:
Samples I tested the IFF loader on:
- st-01/strings6 = base sample and loop are clicky
(I need more checks on this part if you want to help) - st-02/fatbrass = no loop
- st-02/guitar1 = uselessly looping?
- st-17/Afterthought = nice loop
- st-17/badsample = a nice loop from Bad
- st-17/bass.drum = ends with a silent loop ?
- st-17/brass1 = no loop
- st-17/BrassEns.1 = no loop
- st-17/Fantasy2 = nice loop
The ST-17 directory looks like a good one to test IFF properties.