When I slice the linked STL with Slic3r, it doesn't generate a perimeter around the entire set of objects.
This applies to both v1.2.9 and the latest Linux build Slic3r-1.3.0-dev-451f2e3-x86_64.AppImage. Workaround is to split the file into multiple objects using the Split command in Slic3r. But without doing a preview, there's no way to know that the split is needed. In case it's relevant, the STL was generated using OpenSCAD (version 2017.10.18.nightly (git 995fac0).
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