Rhea and Europa low orbit.

#1
These are the last two achievements I need. I can't complete them for some reason. No matter how high or low my orbit is it won't give it to me. And it doesn't help that for some reason the game won't let me speed up more than 3 times if I'm under 500KM. Only happens on those two worlds.
 

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#2
These are the last two achievements I need. I can't complete them for some reason. No matter how high or low my orbit is it won't give it to me. And it doesn't help that for some reason the game won't let me speed up more than 3 times if I'm under 500KM. Only happens on those two worlds.
Since for you to have Rhea, you have to be using a custom solar system, maybe theres an issue with it?