WARNING! Don't upgrade to C6 if you have apps with lookup fields to other apps

WARNING! Don't upgrade to C6 if you have apps with lookup fields to other apps

After many months of being bombarded by the great new "environment" functionality, I could finally migrate to C6 on my Zoho One account. One of the items on the checklist to migrate is "Sandbox enabled in applications". I deleted my sandbox and upgraded, only to find out I couldn't create a production environment after the migration because of "Apps that have dependencies on other apps (for example, lookup to another app)". Basically, migrating will reduce the functionality of your account!

The dependencies are not listed on the support page at the time of writing, but support told me that they are:
  1. Lookup fields to other Creator apps
  2. Functions from other Creator apps
  3. Form embeds from other Creator apps
  4. And to let them know if I find any others
Basically, they don't know if this is the full list, so it could be that you don't have any of these in your app, but still won't be able to create a production environment. Happy gambling!

The development team "is working on a fix, but can't say an exact ETA", as is usual. So you have three options: migrate and only edit in the live version, migrate and stop development (and possibly your business along with it) or don't migrate and keep working in Sandbox. 

BE AWARE!