Have you tried the attached 2.6.17 test build?
Because both say generated by 2.6.16.
You can also disable individual rules (but please test 2.6.17 first, since there shouldn’t be any FPs with it): In HTProtect, open the advanced shield, go to the "Exploit Shield" section, and disable the single rule "Balbooa Gridbox: unauth. file read (uploader.showImage)".
If it still doesn’t work, you can always send me temporary Zugang senden – it’s way easier to solve issues practically than just theoretically.