This slug only works for some message templates. If the order has more than one item, then there will be more than one product ID.
You can use this token:
%Order.Product(s)% and it will list each product in the order, but you cannot capture the Product ID's individually.
I think I understand what you want. I think you want to include a link to this 3rd party website for your customers to write their reviews for each product they purchased, correct?
For example, they provide a link to you like:
http://www.recensioni-verificate.com/verify/customerid=1234&productid=5678
And you want to put this URL in your message template, like this:
http://www.recensioni-verificate.com/verify/customerid=1234&productid=%Product.ID%
Correct?
This won't work.
There are plugins which allow you to automatically send a follow-up email to your customers which does include each product from the order, but with links to your own "Write a review" page using special tokens:
%SmartCampaignOrder.WriteReview(s)%
But this only causes the product names to appear as links to your own website product page...
My suggestion is this:
Buy the
SmartCampaigns plugin.
Create a SmartCampaign for each of your products which you will want customers to review, assigned to just that individual product.
Then, when customers purchase product A, an email can be automatically sent to them asking them to write a review..in the message, you will put the link to the 3rd party site, and the %Product.Id% token will work, because it is the only item.
The only caveat with this methodology that I can see is this:
If a customer buys Product A, Product B, and Product C...they will receive a separate email with the review link for each item they ordered....