Update coming! Brave testers needed!

[Patrik]

If you're using custom models, some of them might behave differently in the update, however fixing this is pretty easy.
You won't have to start over.

Before making any changes to your models, make a backup.
After making your changes, delete the model's msh file.
Basically make sure that your custom models all use a unit scale of 1 meter (you can open the dae file in a text editor and search for <unit and make sure the full line says <unit meter="1" name="meter"></unit>).
And also that the node transforms don't contain any matrices. I don't know how to avoid this when exporting your model, but to fix it after exporting, search in the file for any line beginning with <matrix sid="matrix"> and remove them.