This issue causes any prop to become permanently invisible/unselectable to a player in Creative Edit (cursor wont turn blue to indicate a collision box). A workaround is currently to delete the prop from UEFN (moving it will not show in Creative Edit). This only happens in this version of Creative (not in live).
Repro steps:
-Grab any prop
-Rotate it past its default values
-Place it
-Grab it and reset its rotation
-Place it
-Multi-select it once and wait
-Prop will be gone from Creative Edit