weight and payload isses, I need help.

I just installed the dreamswork q400 and it really works great. It handles just like the q400, very realistic. I think even better than PSS in a lot of ways. I also use the PSS panel and everything works great. The only issues I am having is that it over speeds all the time and under its max speed of 360 kts and that in payload and fuel it says it is overweight... by like 27000 lbs or something crazy like that. Even if I take all of the weight out of payload and all the fuel off, it still remains overweight. Now it doesn't effect its performance but I was wondering is there a way for me to fix the weight issue and the over speed issue and how would I fix that? For example, what would I edit in the aircraft cfg file to give it it's actual proper weight, fuel and balance for the q400 and where would I go to fix the over speed warning?Thank you in advance for any help it the fix.BTW this is for FS2004LB