Applying an upgrade that has an attribute to a wand stops any attributes on the wand changing
Github Report Files.zip

Sorry I completely missed this report and it's been months :(

I see the problem is still there, slotted upgrades completely replace wand properties and don't get merged with any existing properties.

I will need to think on how to improve this.

Well again sorry it took me so long, but this will be fixed in the next dev build:

https://jenkins.elmakers.com/job/MagicPlugin/3918/