Need a 3DMAX expert to fix model ASAP

I have attached model file below , and there are many things need to be fix in order to print
This Design is Bike Headlight
1: first thing needs to be fixed is the lid of the model looks like will fall off easily
please use a better method to make the lid open and close, functional better!

2:There is a inner part of the model to put in hardware
it needs to slide in and out, but right not it cannot functional like a drawer/slider , it looks like will move around inside of the model. please make the structure like drawer slide in and out easily and will not move around or drop.

3: the model body and overall it is too thin, please fix thicker 2mm to 3mm so it will not break easily when 3d print it

4:smooth the model

5; please fix anything that might have error when 3D print

please zip the 3d max files to me and also provide files thta ready to print with 3d printer(for example: obj,stl format..)