This issue has been closed as 'Won't Fix' due to an extended period of time without updates. If this issue is important to you please let us know by posting on the AnswerHub or UDN, and Epic will re-open the ticket for further review.
The Distribution Float Particle Parameter setting for Point Gravity Source "Strength Raw" doesn't accept values being passed into it from Blueprint.
Sphere radius changes however the Point gravity strength doesn't
Both Sphere Radius and Point gravity strength change
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