Here is what I want to achieve - Generate test invoices against copies of test data.

Here are the mountains I've had to climb so far.

1. There's no 'books' sandbox. You have to create a 'Trial'. OK. Created.

2. You can't link that Trial with production data - "Currently you can integrate one Zoho CRM account with any one organization in the Zoho Finance Suite(Zoho Books or Zoho Invoice, Zoho Expense, Zoho Subscriptions, Zoho Inventory) organization."

3. OK, so I guess I have to link it to sandbox? There's no way to 'backup and restore' my data into a completely new CRM org, so that MUST be the right way, right? (No. Wrong. This is where things STARTED going wrong)

4. There is no way to back up and restore production data into a sandbox. So I had to write a tool to do that, and now I have data in CRM Sandbox. (This was amazingly annoying to do through the APIs, but would have been TRIVIAL for Zoho to do through their backend, talking directly to their databases)

5. I go into my Sandbox and create a ZSC Key, as there's none there (good news, right?) - I did this by replacing 'crm' with crmsandbox, giving me the URL https://crmsandbox.zoho.com/crm/org690597351/settings/zsc-key  (Note - that's the correct org id of the sandbox, please don't ask for it again)

6. I go into my Trial Books org, and try to import the ZSC Key anddddd.. SURPRISE!

Currently you can integrate one Zoho CRM account with any one organization in the Zoho Finance Suite(Zoho Books or Zoho Invoice, Zoho Expense, Zoho Subscriptions, Zoho Inventory) organization. This Zoho CRM account is already integrated with the organization (etc etc)

So. Seriously, what is the go here? How am I meant to actually test anything if there's no testing environments?

Have I missed something obvious?  Is there some secret way to restore data into a new org? I am kinda curious as to why you even provide a backup option, if there's no way to restore it.  I guess you could take those CSVs that are backed up and GUESS what maps to what, but that doesn't contain the module layouts or anything, and there is no way to get from that backup to a working system without days and days of work.