When working in an assembly, I edit a part, create new sketch and project geometry to the sketch plane. Sometimes the geometry appears with the color yellow and will move location when the original geometry is moved. Sometimes the geometry appears with the color blue and will have the Locked Constraints with it. This geometry WILL NOT move when the original geometry is moved. Can anyone tell me why?
The reason being is because when an object (part, or assembly) isn't fully constrained within an assembly, it can be moved and dragged around. If you move them, the sketch moves with whatever you moved. If a part or assembly is fully constrained, the sketch will not move unless the surface or part that is being sketched on is moved.
This is a standard with any design software. The best way to go about this is rather than edit a part using sketches in assembly, you edit the part individually by opening it, or right clicking the part and then click edit. Editing within an assembly file is never a good practice. The edits you make there do not directly effect the part files themselves. Only what appears in the assembly file.
I see what has happened. This is a problem that is very common. What has happened is you are referencing geometry from another part in an assembly. This is something you want to avoid at all costs and is what is creating your problem. Since the left and right side parts are practically the same, you can save a copy of the left side part, mirror it, and then save that as the right side part since they are identical on the inside face. That would solve one problem. The left side part is referencing the bottom plate part also. Changes in the bottom plate, change part other parts also. This can also cause it to be unconstrained. Whenever making parts, NEVER (if possible) reference geometry from another part in an assembly for future reference. That is what the rotation symbol in the feature tree means. I will fix this for you and post parts shortly.