That error is a simple fix, it's caused when somebody leaves to soon after certain code to give the arrest stick is called. It's my mistake that I haven't put a valid check in there yet. I still don't know how to fix the other problem, I can't recreate it.
I am writing the biggest assignment of the year at my school at the moment, and I have my driving test this same week. I have no time to figure this problem out. Hold on and be patient. The fix will come when I have time to look into the issue.
Sounds really odd. I will take a look at it as soon as possible. Is it correct that you all use 2.5.1? Can you please confirm that it is actually 2.5.1. You can see it in the darkrp.txt file under "Version"