You need to work on pulling your shoulders back and down while pushing your chest out and up in the starting position and hold it through the first and second pull. If you pull with a rounded back and shoulders forward the bar is bound to end up in front of you.
With regards to grip width it's real easy, just grab the bar and stand tall with your chest up and shoulders back and dip about 5-10 cm. At this position the bar should be directly in the hip crease so if it's not adjust your grip accordingly.
The bending of your arms might be easily fixed by simply rotating your elbows forward in the starting position. I use this method on lifters all the time and it usually solves the problem immediately.