Loading these files appears to product either noise or random modulation/artifacts.
The issue appeared to be mixing up two frequency tables, the freq and the wavestep tables.
Attached is a single file that should resolve the problem and I would be pleased if you could test it.
The remains an issue which is tuning of the scales: if there are 12 notes in an octave then it may be feasible to have the synth 'Tune' control work. If there are 19 then I could assume this is a mapping of 'flat flat' and do the same. I cannot make assumptions of how to tune scala files with other numbers of notes and so the net is that the Tune control does not work if you have a Scala active. This was always the case with the bristol implementation.
You can advise me on that issue perrhaps.
Another potential issue is that I tested this with a couple of sample files from the set and I have a feeling I am 1/2 tone out on my mappings - that is difficult to say without a better knowledge of the specific scales so I am leaving this for later.
The attached file goes in bristol-0.60.8/bristol and another 'make install'.
Scale file correction #1 for 0.60.8
Fix was delivered in 0.60.9