This problem was actually fixed a few releases ago R121. I intended to update this post but forgot until now. Sorry about that.
R121 release notes
specifically these two changes.
Change
Possibly breaking change: Sin behavior now updates position just before the events run, rather than just after. This allows for objects using set position to follow without lag. However this means events can now override the position which could cause existing projects to work differently. Please watch out for anything breaking.
Change
Possibly breaking change: Platform behavior now should follow moving platforms using the Sine behavior without any lag. However since the sequence it runs has changed, it may also cause existing projects to work differently; please watch out for anything breakin
Here is a link to the exact same demo as my first post but now exported from the most recent release.
Original Demo exported from R123.2