So here's the scenario - you are either bad at importing 3D models, can't be bothered or think its easier to mix models in Alice. Instead of trawling the web for models, or creating your own ones you decide to just make something up out of the objects and shapes in the Alice gallery.
Then you hit an issue - you cannot merge these objects, you cannot create subparts - they are not part of one object. This has especially bad implications if you want to export the model as one piece to be used again.
So here is my solution: as part of my project I am developing I have designed a simple UI that allows objects to be glued together.
I call it Gloo.
Really simple to use, just go to the Tools > Gloo menu at the top of Alice and click to Gloo. A nice dialog box pops up, just type in the parent and as many objects as you would like to glue to it as you want. Confirm it and viola.
Easy as that.
Now you can right click on the parent object and go to save object... to export it and it will save with all the glued on objects attached.
While I am not yet ready to release this yet, I can provide two screenshots and a compound object. This is Chris101b's motorbike from his video "War Zone", it originally consisted of several models, but I glued them altogether and it should import nicely as one.