While this may not be quite so polished, it may get you out of a tight spot if you just MUST apply some modifier to Particles...hence they have to be turned to mesh.
Sorry, Max 2018 ONLY.
Installation:
https://knowledge.autodesk.com/support/3ds-max/learn-explore/caas/CloudH...
(or drag n drop...whatever)
Then can be found as PMesh in modifier dropdown list)
