Collimation is easy. This video is made by Orion but all Newtonian scopes are collimated in a similar fashion. I use the collimation cap included with may Orion XT8i which is similar to the scope they use in the video. Your do will be done in a similar manner.
How to Collimate an Orion Dob using a Collimation cap or laser
https://www.youtube.com/watch?v=YAVGcGEBmCE
Stray light with a collapsable dob is going to be a problem. I would expect the shroud will help.
Form my solid tube dob I have a flexible dew shield at the end which helps with dew and with stray light.
As for the cross effect or shooting rays, I get that too. I think you will find this can be caused by the lack of transparency in the atmosphere. High humidity, light pollution and the like will cause this as the particles in the atmosphere scatter the light from the bright planets. You probably notice it less on stars but if the atmosphere is not truly clear you will probably still get some of this.