No it does not default to heating the bed, and are you 100% sure that when you select the Quick print mode it stays or sticks to that selection? Sounds like its going to a set point for ABS. No a STL file can not change settings unless its gcode instead?
Did you try to make the adjustments in the machine area? Those seem to override the gcode settings in whatever your doing.
Use the new Cura downloaded from the website, I think its 15.xx. Why? Because when you select the expert mode it copies over the Quick print perimeters or settings. Then in the Expert mode you can enter the temperature as needed.
Also in the Machine mode, you can see actual temperatures, both the set point and actual temps.