Most of the time I think it is an advantage that the software selects feed rates. I can imagine the learning curve for setting these yourself (as with other CNC machines) would likely be non-trivial. I suspect novice users especially would have problems with setting incorrect feed rates. But yes in this case the software may be at fault, and having the ability to change a default setting would be one answer. Good luck and please keep us informed of the outcome, as I'm sure others are also having this problem.