Another strange thing i´ve notice is that there are certain ships that you can´t even mark them (lock on target) is like if they don´t exist, for example:
http://img4.imageshack.us/img4/6450/cantmark.jpg
Another one:
http://img825.imageshack.us/img825/3168/anotherones.jpg
BTW i´m having this problem with the trees, i´m using "small trees" mod now but with stock ones is the same. Any advice for my graphic card settings or whatever??