When connecting a populated Set variable to the target pin of a blueprint node, for instance, SetRelativeLocationAndRotation, somehow this triggers a crash due to a failed assert in the FScriptSetHelper class, specifically:
void DestructItems(int32 Index, int32 Count)
{
check(Index >= 0);
check(Count >= 0); // <-- this fails and crashes
if (Count == 0)
{
return;
}