The newest version of Unofficial Skyrim Patch (2.1.2 posted on 27 June 2015) isn't playing well with Dual Sheath Redux. The SkyProc patcher thows out the error that Unofficial Skyrim Patch.esp is missing or not installed. According to some forums it is because of USKP 2.1.2s header being too long. Using USKP 2.1.1 apparently fixes this problem, but without a trusted source for the file I am unable to run STEP.