it was discussed earlier in the forum, as I remember it can be solved perfectly only if you use custom slpines for movement, the built in one will always result in what you experienced, unless you put them in equal distances. but maybe somebody else has a better answer than me.
1. If my entity going backwards along a circle path and the distance is negative (from first point to last point), than my entity "fly away" from the path and dont follow it. But why?