Swim's experience is w/ A/B's as appose to STB's....so i don't know how much help he'll be, but he can guarentee that it has nothing to do with the bark being 100% prepowdered.
It can possibly a fat or tannin in the park that got carried over to SWIY's naptha. Most people see this as being an unnessisary (splng?) step, but swim alway's defats.....even though mhrb is not suppose to be fatty,i think that's a general truth but that's not alway's the case.Still that shouldn't discolor the naptha.
here is a link that you might find useful.....someone with a similar issue.
http://www.dmt-nexus.me/....aspx?g=posts&t=5866 As far as the reddish color....swim sais carry on with the tek as normal and at the end, mabey re-x a couple times to get rid of any unwanted contaminates that carried over to your naptha.
Also, start trying some A/B extractions, it usually yields much cleaner product and they are not that difficult. Swims first extraction was with marsofold tek and he go nice white crystals in less than 24 hrs.
Good luck
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