I agree that the components need to be sorted, I've weighed in on this for some time now..
But in the mean time until it is sorted, I follow some rules I've developed as I still use components a lot. I get no problems now.
1. I always create my components in a separate file and use "import component" into my project. The origin is important.
2. Right click the component in the component manager and select "always update".
3. In the separate component file I always name the layer the same as the component so it sits in it's own layer in the main model and I know what's what.
4. If you don't want the component to alway face the camera, make sure to choose 'fixed" in the tool options parameters.
I got caught out a couple of times where, say for example I use a bollard component which looks the same from any direction but I forgot to turn on fixed rotation. They turn to the camera and really slow down the model. I think it should be set to "Fixed Rotation" by default.
5. Make sure your file paths are not changed after inserting components, that goes for everything like materials and textures.
Most of this probably goes without saying, it's mostly for newer users of components, but if you follow these rules they should behave.
Another tip is:
Create a "placement component", say a low resolution circle and call it something you remember.
If you get the warning that any other component is different etc. Use the "Replace components" tool on the component to change to the circle component.
Delete the problem component, re-import the component from it's file and replace the circle component with that. Your warnings will now stop.
Ok, I think I broke the record for saying "component" the most times in one post
Hope this helps,