thats true the going up part is bugy but it also safed my rover a few times :D
there is work todo no question asked but getting rid of random thruster failures isnt the solution
the going up thing seems like the lander/rover has some sort of problem with the landing side or its relativ velocity, i allways safe in the first few moments of descent if its a bad run hit load and do it again

its intentionally and somewaht random like iRL you never now if your lander/rover is going to make it